1
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Ackerman MJ, Giudicessi JR. Continuous variant reclassification: An effective tool in the ongoing quest to escape genetic purgatory. Heart Rhythm 2024:S1547-5271(24)00104-8. [PMID: 38307312 DOI: 10.1016/j.hrthm.2024.01.050] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/25/2024] [Accepted: 01/26/2024] [Indexed: 02/04/2024]
Affiliation(s)
- Michael J Ackerman
- Department of Cardiovascular Medicine, Windland Smith Rice Genetic Heart Rhythm Clinic, Mayo Clinic, Rochester, Minnesota; Department of Molecular Pharmacology and Experimental Therapeutics, Windland Smith Rice Sudden Death Genomics Laboratory, Mayo Clinic, Rochester, Minnesota; Department of Pediatric and Adolescent Medicine, Division of Pediatric Cardiology, Mayo Clinic, Rochester, Minnesota
| | - John R Giudicessi
- Department of Cardiovascular Medicine, Windland Smith Rice Genetic Heart Rhythm Clinic, Mayo Clinic, Rochester, Minnesota; Department of Molecular Pharmacology and Experimental Therapeutics, Windland Smith Rice Sudden Death Genomics Laboratory, Mayo Clinic, Rochester, Minnesota.
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2
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Novelli V, Faultless T, Cerrone M, Care M, Manzoni M, Bober SL, Adler A, De-Giorgio F, Spears D, Gollob MH. Enhancing the interpretation of genetic observations in KCNQ1 in unselected populations: relevance to secondary findings. Europace 2023; 25:euad317. [PMID: 37897496 PMCID: PMC10637310 DOI: 10.1093/europace/euad317] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2023] [Accepted: 10/11/2023] [Indexed: 10/30/2023] Open
Abstract
AIMS Rare variants in the KCNQ1 gene are found in the healthy population to a much greater extent than the prevalence of Long QT Syndrome type 1 (LQTS1). This observation creates challenges in the interpretation of KCNQ1 rare variants that may be identified as secondary findings in whole exome sequencing.This study sought to identify missense variants within sub-domains of the KCNQ1-encoded Kv7.1 potassium channel that would be highly predictive of disease in the context of secondary findings. METHODS AND RESULTS We established a set of KCNQ1 variants reported in over 3700 patients with diagnosed or suspected LQTS sent for clinical genetic testing and compared the domain-specific location of identified variants to those observed in an unselected population of 140 000 individuals. We identified three regions that showed a significant enrichment of KCNQ1 variants associated with LQTS at an odds ratio (OR) >2: the pore region, and the adjacent 5th (S5) and 6th (S6) transmembrane (TM) regions. An additional segment within the carboxyl terminus of Kv7.1, conserved region 2 (CR2), also showed an increased OR of disease association. Furthermore, the TM spanning S5-Pore-S6 region correlated with a significant increase in cardiac events. CONCLUSION Rare missense variants with a clear phenotype of LQTS have a high likelihood to be present within the pore and adjacent TM segments (S5-Pore-S6) and a greater tendency to be present within CR2. This data will enhance interpretation of secondary findings within the KCNQ1 gene. Further, our data support a more severe phenotype in LQTS patients with variants within the S5-Pore-S6 region.
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Affiliation(s)
- Valeria Novelli
- Centro Cardiologico Monzino, IRCCS, Via C. Parea 4, Milano, 20138, Italy
| | - Trent Faultless
- Toronto General Hospital Research Institute, University of Toronto, Toronto, Canada
| | - Marina Cerrone
- Inherited Arrhythmia Clinic and Heart Rhythm Center, ‘Leon Charney’ Division of Cardiology NYU Grossman School of Medicine, NewYork, NY, USA
| | - Melanie Care
- Inherited Arrhythmia and Cardiomyopathy Program, Division of Cardiology, University of Toronto, 200 Elizabeth St.Rm 3GW-360, Toronto M5G 2C4, Ontario, Canada
| | - Martina Manzoni
- Centro Cardiologico Monzino, IRCCS, Via C. Parea 4, Milano, 20138, Italy
| | - Sara L Bober
- Toronto General Hospital Research Institute, University of Toronto, Toronto, Canada
| | - Arnon Adler
- Toronto General Hospital Research Institute, University of Toronto, Toronto, Canada
| | - Fabio De-Giorgio
- Department of Health Care Surveillance and Bioethics, Section of Legal Medicine, Fondazione Policlinico A.Gemelli IRCCS,Università Cattolica del Sacro Cuore, 00168, Rome, Italy
| | - Danna Spears
- Inherited Arrhythmia and Cardiomyopathy Program, Division of Cardiology, University of Toronto, 200 Elizabeth St.Rm 3GW-360, Toronto M5G 2C4, Ontario, Canada
| | - Michael H Gollob
- Toronto General Hospital Research Institute, University of Toronto, Toronto, Canada
- Inherited Arrhythmia and Cardiomyopathy Program, Division of Cardiology, University of Toronto, 200 Elizabeth St.Rm 3GW-360, Toronto M5G 2C4, Ontario, Canada
- Department of Physiology, University of Toronto, Toronto, Canada
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3
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Josephs KS, Roberts AM, Theotokis P, Walsh R, Ostrowski PJ, Edwards M, Fleming A, Thaxton C, Roberts JD, Care M, Zareba W, Adler A, Sturm AC, Tadros R, Novelli V, Owens E, Bronicki L, Jarinova O, Callewaert B, Peters S, Lumbers T, Jordan E, Asatryan B, Krishnan N, Hershberger RE, Chahal CAA, Landstrom AP, James C, McNally EM, Judge DP, van Tintelen P, Wilde A, Gollob M, Ingles J, Ware JS. Beyond gene-disease validity: capturing structured data on inheritance, allelic requirement, disease-relevant variant classes, and disease mechanism for inherited cardiac conditions. Genome Med 2023; 15:86. [PMID: 37872640 PMCID: PMC10594882 DOI: 10.1186/s13073-023-01246-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Accepted: 10/12/2023] [Indexed: 10/25/2023] Open
Abstract
BACKGROUND As the availability of genomic testing grows, variant interpretation will increasingly be performed by genomic generalists, rather than domain-specific experts. Demand is rising for laboratories to accurately classify variants in inherited cardiac condition (ICC) genes, including secondary findings. METHODS We analyse evidence for inheritance patterns, allelic requirement, disease mechanism and disease-relevant variant classes for 65 ClinGen-curated ICC gene-disease pairs. We present this information for the first time in a structured dataset, CardiacG2P, and assess application in genomic variant filtering. RESULTS For 36/65 gene-disease pairs, loss of function is not an established disease mechanism, and protein truncating variants are not known to be pathogenic. Using the CardiacG2P dataset as an initial variant filter allows for efficient variant prioritisation whilst maintaining a high sensitivity for retaining pathogenic variants compared with two other variant filtering approaches. CONCLUSIONS Access to evidence-based structured data representing disease mechanism and allelic requirement aids variant filtering and analysis and is a pre-requisite for scalable genomic testing.
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Affiliation(s)
- Katherine S Josephs
- National Heart and Lung Institute, Imperial College London, Du Cane Road, London, W12 0NN, UK
- Royal Brompton and Harefield Hospitals, Guy's and St Thomas' NHS Foundation Trust, London, UK
| | - Angharad M Roberts
- National Heart and Lung Institute, Imperial College London, Du Cane Road, London, W12 0NN, UK
- Great Ormond Street Hospital, NHS Foundation Trust, London, UK
| | - Pantazis Theotokis
- National Heart and Lung Institute, Imperial College London, Du Cane Road, London, W12 0NN, UK
| | - Roddy Walsh
- Amsterdam University Medical Centre, University of Amsterdam, Heart Center, Department of Experimental Cardiology, Amsterdam Cardiovascular Sciences, Amsterdam, The Netherlands
| | | | - Matthew Edwards
- Clinical Genetics & Genomics Lab, Royal Brompton and Harefield Hospitals, Guy's and St Thomas' NHS Foundation Trust, London, UK
| | - Andrew Fleming
- Clinical Genetics & Genomics Lab, Royal Brompton and Harefield Hospitals, Guy's and St Thomas' NHS Foundation Trust, London, UK
| | - Courtney Thaxton
- Department of Genetics, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Jason D Roberts
- Population Health Research Institute, McMaster University, and Hamilton Health Sciences, Hamilton, Ontario, Canada
| | - Melanie Care
- Department of Molecular Genetics, University of Toronto, Toronto, Canada
- Division of Cardiology, Toronto General Hospital, Toronto, Canada
| | - Wojciech Zareba
- Clinical Cardiovascular Research Center, University of Rochester, Rochester, NY, USA
| | - Arnon Adler
- Division of Cardiology, Peter Munk Cardiac Centre, University Health Network and Department of Medicine, University of Toronto, Toronto, Ontario, Canada
| | | | - Rafik Tadros
- Cardiovascular Genetics Center, Montreal Heart Institute, and Faculty of Medicine, Université de Montréal, Montreal, Canada
| | - Valeria Novelli
- Unit of Immunology and Functional Genomics, Centro Cardiologico Monzino IRCCS, Milano, Italy
| | - Emma Owens
- Department of Genetics, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Lucas Bronicki
- Department of Pathology and Laboratory Medicine, University of Ottawa, Ottawa, Ontario, Canada
- Department of Genetics, CHEO, Ottawa, Ontario, Canada
| | - Olga Jarinova
- Department of Pathology and Laboratory Medicine, University of Ottawa, Ottawa, Ontario, Canada
- Department of Genetics, CHEO, Ottawa, Ontario, Canada
| | - Bert Callewaert
- Center for Medical Genetics, Ghent University Hospital, Ghent, Belgium
- Department of Biomolecular Medicine, Ghent University, Ghent, Belgium
| | - Stacey Peters
- Department of Cardiology and Genomic Medicine, Royal Melbourne Hospital, Melbourne, Australia
- University of Melbourne, Melbourne, Australia
| | - Tom Lumbers
- Barts Health & University College London Hospitals NHS Trusts, London, UK
- Institute of Health Informatics, University College London, London, UK
| | - Elizabeth Jordan
- Divisions of Human Genetics and Cardiovascular Medicine, The Ohio State University, Columbus, OH, USA
| | - Babken Asatryan
- Department of Cardiology, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
- Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Neesha Krishnan
- Centre for Population Genomics, Garvan Institute of Medical Research, and UNSW Sydney, Sydney, Australia
| | - Ray E Hershberger
- Divisions of Human Genetics and Cardiovascular Medicine, The Ohio State University, Columbus, OH, USA
| | - C Anwar A Chahal
- Center for Inherited Cardiovascular Diseases, WellSpan Health, Lancaster, PA, USA
- Cardiac Electrophysiology and Inherited Cardiovascular Diseases, Cardiovascular Division, Hospital of the University of Pennsylvania, Philadelphia, PA, USA
- Department of Cardiovascular Medicine, Mayo Clinic, Rochester, MN, USA
- Barts Heart Centre, St Bartholomew's Hospital, Barts Health NHS Trust, London, UK
| | - Andrew P Landstrom
- Department of Pediatrics and Cell Biology, Duke University School of Medicine, Durham, NC, USA
| | - Cynthia James
- Johns Hopkins Center for Inherited Heart Diseases, Department of Medicine, Johns Hopkins University, Baltimore, MD, USA
| | - Elizabeth M McNally
- Center for Genetic Medicine, Dept of Medicine (Cardiology), Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - Daniel P Judge
- Medical University of South Carolina, Charleston, SC, USA
| | - Peter van Tintelen
- Department of Genetics, University Medical Center Utrecht, Utrecht, the Netherlands
| | - Arthur Wilde
- Department of Cardiology, Amsterdam UMC location University of Amsterdam, Meibergdreef 9, Amsterdam, the Netherlands
- Amsterdam Cardiovascular Sciences, Heart Failure and Arrhythmias, Amsterdam UMC location University of Amsterdam, Amsterdam, the Netherlands
| | - Michael Gollob
- Inherited Arrhythmia and Cardiomyopathy Program, Division of Cardiology, University of Toronto, Toronto, ON, Canada
| | - Jodie Ingles
- Centre for Population Genomics, Garvan Institute of Medical Research, and UNSW Sydney, Sydney, Australia
| | - James S Ware
- National Heart and Lung Institute, Imperial College London, Du Cane Road, London, W12 0NN, UK.
- Royal Brompton and Harefield Hospitals, Guy's and St Thomas' NHS Foundation Trust, London, UK.
- MRC London Institute of Medical Sciences, Imperial College London, London, UK.
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4
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Ke Z, Li C, Bai G, Tan L, Wang J, Zhou M, Zhou J, Chen SY, Dong X. KCNH2 mutation c.3099_3112del causes congenital long QT syndrome type 2 with gender differences. Clinics (Sao Paulo) 2023; 78:100285. [PMID: 37783170 PMCID: PMC10562146 DOI: 10.1016/j.clinsp.2023.100285] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/03/2023] [Revised: 08/24/2023] [Accepted: 09/04/2023] [Indexed: 10/04/2023] Open
Abstract
INTRODUCTION Long QT Syndrome (LQTS) is an inherited disease with an abnormal electrical conduction system in the heart that can cause sudden death as a result of QT prolongation. LQT2 is the second most common subtype of LQTS caused by loss of function mutations in the potassium voltage-gated channel subfamily H member 2 (KCNH2) gene. Although more than 900 mutations are associated with the LQTS, many of these mutations are not validated or characterized. METHODS AND RESULTS Sequencing analyses of genomic DNA of a family with LQT2 identified a putative mutation. i.e., KCNH2(NM_000238.3): c.3099_3112del, in KCNH2 gene which appeared to be a definite pathogenic mutation. The family pedigree information showed a gender difference in clinical features and T-wave morphology between male and female patients. The female with mutation exhibited recurring ventricular arrhythmia and syncope, while two male carriers did not show any symptoms. In addition, T-wave in females was much flatter than in males. The female proband showed a positive reaction to the lidocaine test. Lidocaine injection almost completely blocked ventricular arrhythmia and shortened the QT interval by ≥30 ms. Treatment with propranolol, mexiletine, and implantation of cardioverter-defibrillators prevented the sustained ventricular tachycardia, ventricular fibrillation, and syncope, as assessed by a 3-year follow-up evaluation. CONCLUSIONS A putative mutation c.3099_3112del in the KCNH2 gene causes LQT2 syndrome, and the pathogenic mutation mainly causes symptoms in female progeny.
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Affiliation(s)
- ZunPing Ke
- School of Public Health, Hubei University of Medicine, China
| | - Chao Li
- Children's Medical Center, Taihe Hospital, Hubei University of Medicine, China
| | - Gang Bai
- Department of Ultrasonics, Taihe Hospital, Hubei University of Medicine, China
| | - Li Tan
- Cardiovascular Center, Taihe Hospital, Hubei University of Medicine, China
| | - JunFeng Wang
- Cardiovascular Center, Taihe Hospital, Hubei University of Medicine, China
| | - Ming Zhou
- Cardiovascular Center, Taihe Hospital, Hubei University of Medicine, China
| | - JianHua Zhou
- Cardiovascular Center, Taihe Hospital, Hubei University of Medicine, China
| | - Shi-You Chen
- Department of Surgery, University of Missouri School of Medicine, Columbia, MO, USA
| | - Xiao Dong
- Cardiovascular Center, Taihe Hospital, Hubei University of Medicine, China; Department of Surgery, University of Missouri School of Medicine, Columbia, MO, USA.
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5
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Immadisetty K, Fang X, Ramon GS, Hartle CM, McCoy TP, Center RG, Mirshahi T, Delisle BP, Kekenes-Huskey PM. Prediction of Kv11.1 potassium channel PAS-domain variants trafficking via machine learning. J Mol Cell Cardiol 2023; 180:69-83. [PMID: 37187232 DOI: 10.1016/j.yjmcc.2023.05.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/07/2022] [Revised: 04/28/2023] [Accepted: 05/09/2023] [Indexed: 05/17/2023]
Abstract
Congenital long QT syndrome (LQTS) is characterized by a prolonged QT-interval on an electrocardiogram (ECG). An abnormal prolongation in the QT-interval increases the risk for fatal arrhythmias. Genetic variants in several different cardiac ion channel genes, including KCNH2, are known to cause LQTS. Here, we evaluated whether structure-based molecular dynamics (MD) simulations and machine learning (ML) could improve the identification of missense variants in LQTS-linked genes. To do this, we investigated KCNH2 missense variants in the Kv11.1 channel protein shown to have wild type (WT) like or class II (trafficking-deficient) phenotypes in vitro. We focused on KCNH2 missense variants that disrupt normal Kv11.1 channel protein trafficking, as it is the most common phenotype for LQTS-associated variants. Specifically, we used computational techniques to correlate structural and dynamic changes in the Kv11.1 channel protein PAS domain (PASD) with Kv11.1 channel protein trafficking phenotypes. These simulations unveiled several molecular features, including the numbers of hydrating waters and hydrogen bonding pairs, as well as folding free energy scores, that are predictive of trafficking. We then used statistical and machine learning (ML) (Decision tree (DT), Random forest (RF), and Support vector machine (SVM)) techniques to classify variants using these simulation-derived features. Together with bioinformatics data, such as sequence conservation and folding energies, we were able to predict with reasonable accuracy (≈75%) which KCNH2 variants do not traffic normally. We conclude that structure-based simulations of KCNH2 variants localized to the Kv11.1 channel PASD led to an improvement in classification accuracy. Therefore, this approach should be considered to complement the classification of variant of unknown significance (VUS) in the Kv11.1 channel PASD.
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Affiliation(s)
| | - Xuan Fang
- Stritch School of Medicine, Loyola University Chicago, Maywood, IL, USA
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6
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Alghamdi F, Alharbi A, Mohamed F, Alghamdi A, Bashir S. Clinical phenotype associated with variants in TANGO2: A case study. Arch Pediatr 2023:S0929-693X(23)00097-0. [PMID: 37394363 DOI: 10.1016/j.arcped.2023.04.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2022] [Revised: 02/16/2023] [Accepted: 04/29/2023] [Indexed: 07/04/2023]
Abstract
Transport and Golgi organization 2 (TANGO2) disease is a severe inherited disorder that presents with multiple symptoms and a broad spectrum of phenotypes, including metabolic crisis, encephalopathy, cardiac arrhythmia, and hypothyroidism. The clinical picture of a TANGO2 gene biallelic mutation involves encephalopathy and rhabdomyolysis and is marked by cardiac rhythm disorders and neurological regression. The presentation of encephalopathy varies and can range from isolated language delay and cognitive impairment to multiple disabilities and spastic quadriparesis. A TANGO2 gene mutation causes serious illness with a limited life expectancy due to the unpredictable risk of cardiac rhythm disorder and death, particularly during rhabdomyolysis. Clinicians must therefore consider the TANGO2 gene when confronted with rhabdomyolysis in a patient suffering from an early developmental disorder. Currently, managing this disease is purely symptomatic. Here, we report the clinical features of a 10-year-old girl with mutations in the TANGO2 gene. Unique to our case was the lack of elevated creatine kinase during the early acute crises of cardiac failure and multi-organ failure, as well as the lack of any prior mental retardation associated with the aberrant heart rhythm.
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Affiliation(s)
- Fouad Alghamdi
- Pediatric Neurology Department, King Fahad Specialist Hospital, Dammam, Saudi Arabia.
| | - Alanoud Alharbi
- Pediatric Neurology Department, King Fahad Specialist Hospital, Dammam, Saudi Arabia
| | - Fatema Mohamed
- Pediatric Neurology Department, King Fahad Specialist Hospital, Dammam, Saudi Arabia
| | - Alaa Alghamdi
- King Fahad University Hospital, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia
| | - Shahid Bashir
- Neuroscience Center, King Fahad Specialist Hospital, Dammam, Saudi Arabia
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7
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Josephs KS, Roberts AM, Theotokis P, Walsh R, Ostrowski PJ, Edwards M, Fleming A, Thaxton C, Roberts JD, Care M, Zareba W, Adler A, Sturm AC, Tadros R, Novelli V, Owens E, Bronicki L, Jarinova O, Callewaert B, Peters S, Lumbers T, Jordan E, Asatryan B, Krishnan N, Hershberger RE, Chahal CAA, Landstrom AP, James C, McNally EM, Judge DP, van Tintelen P, Wilde A, Gollob M, Ingles J, Ware JS. Beyond gene-disease validity: capturing structured data on inheritance, allelic-requirement, disease-relevant variant classes, and disease mechanism for inherited cardiac conditions. MEDRXIV : THE PREPRINT SERVER FOR HEALTH SCIENCES 2023:2023.04.03.23287612. [PMID: 37066275 PMCID: PMC10104233 DOI: 10.1101/2023.04.03.23287612] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 04/29/2023]
Abstract
Background As availability of genomic testing grows, variant interpretation will increasingly be performed by genomic generalists, rather than domain-specific experts. Demand is rising for laboratories to accurately classify variants in inherited cardiac condition (ICC) genes, including as secondary findings. Methods We analyse evidence for inheritance patterns, allelic requirement, disease mechanism and disease-relevant variant classes for 65 ClinGen-curated ICC gene-disease pairs. We present this information for the first time in a structured dataset, CardiacG2P, and assess application in genomic variant filtering. Results For 36/65 gene-disease pairs, loss-of-function is not an established disease mechanism, and protein truncating variants are not known to be pathogenic. Using CardiacG2P as an initial variant filter allows for efficient variant prioritisation whilst maintaining a high sensitivity for retaining pathogenic variants compared with two other variant filtering approaches. Conclusions Access to evidence-based structured data representing disease mechanism and allelic requirement aids variant filtering and analysis and is pre-requisite for scalable genomic testing.
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Affiliation(s)
- Katherine S Josephs
- National Heart and Lung Institute, Imperial College London, London, UK
- Royal Brompton and Harefield Hospitals, Guy's and St Thomas' NHS Foundation Trust, London UK
| | - Angharad M Roberts
- National Heart and Lung Institute, Imperial College London, London, UK
- Great Ormond Street Hospital NHS Foundation Trust, London, UK
| | | | - Roddy Walsh
- Amsterdam University Medical Centre, University of Amsterdam, Heart Center, Department of Experimental Cardiology, Amsterdam Cardiovascular Sciences, Amsterdam, The Netherlands
| | | | - Matthew Edwards
- Clinical Genetics & Genomics Lab, Royal Brompton and Harefield Hospitals, Guy's and St Thomas' NHS Foundation Trust, London UK
| | - Andrew Fleming
- Clinical Genetics & Genomics Lab, Royal Brompton and Harefield Hospitals, Guy's and St Thomas' NHS Foundation Trust, London UK
| | - Courtney Thaxton
- Department of Genetics, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Jason D Roberts
- Population Health Research Institute, McMaster University, and Hamilton Health Sciences, Hamilton, Ontario, Canada
| | - Melanie Care
- Department of Molecular Genetics, University of Toronto, Toronto, Canada
- Division of Cardiology, Toronto General Hospital, Toronto, Canada
| | - Wojciech Zareba
- Clinical Cardiovascular Research Center, University of Rochester, Rochester, New York, USA
| | - Arnon Adler
- Division of Cardiology, Peter Munk Cardiac Centre, University Health Network and Department of Medicine, University of Toronto, Toronto, ON, Canada
| | - Amy C Sturm
- 23andMe, Sunnyvale, California, Genomic Health
| | - Rafik Tadros
- Cardiovascular Genetics Center, Montreal Heart Institute, and Faculty of Medicine, Université de Montréal
| | - Valeria Novelli
- Unit of Immunology and Functional Genomics, Centro Cardiologico Monzino IRCCS, Milano, Italy
| | - Emma Owens
- Department of Genetics, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Lucas Bronicki
- CHEO Research Institute, University of Ottawa, Ontario, Canada
| | - Olga Jarinova
- CHEO Research Institute, University of Ottawa, Ontario, Canada
- Department of Genetics, CHEO, Ontario, Canada
| | - Bert Callewaert
- Center for Medical Genetics, Ghent University Hospital
- Department of Biomolecular Medicine, Ghent University
| | - Stacey Peters
- Department of Cardiology and Genomic Medicine, Royal Melbourne Hospital, Melbourne, Australia
- University of Melbourne, Melbourne, Australia
| | - Tom Lumbers
- Barts Health & University College London Hospitals NHS Trusts, London, UK
- Institute of Health Informatics, University College London, London, UK
| | - Elizabeth Jordan
- Division of Human Genetics, The Ohio State University, Columbus, Ohio USA
| | - Babken Asatryan
- Department of Cardiology, Inselspital, Bern University Hospital, University of Bern, Bern, Switzerland
- Division of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Neesha Krishnan
- Centre for Population Genomics, Garvan Institute of Medical Research, and UNSW Sydney, Sydney, Australia
| | - Ray E Hershberger
- Division of Human Genetics, The Ohio State University, Columbus, Ohio USA
| | - C Anwar A Chahal
- Center for Inherited Cardiovascular Diseases, WellSpan Health, Lancaster, PA USA
- Cardiac Electrophysiology and Inherited Cardiovascular Diseases, Cardiovascular Division, Hospital of the University of Pennsylvania, Philadelphia, PA USA
- Department of Cardiovascular Medicine, Mayo Clinic, Rochester, MN USA
- Barts Heart Centre, St Bartholomew's Hospital, Barts Health NHS Trust, London, UK
| | - Andrew P Landstrom
- Department of Pediatrics and Cell Biology, Duke University School of Medicine, Durham, North Carolina, US
| | - Cynthia James
- Johns Hopkins Center for Inherited Heart Diseases, Department of Medicine, Johns Hopkins
| | - Elizabeth M McNally
- Center for Genetic Medicine, Dept of Medicine (Cardiology), Northwestern University Feinberg School of Medicine, Chicago, IL US
| | - Daniel P Judge
- Medical University of South Carolina, Charleston, SC USA
| | - Peter van Tintelen
- Department of Genetics, University Medical Center Utrecht, Utrecht, the Netherlands
| | - Arthur Wilde
- Amsterdam UMC location University of Amsterdam, Department of Cardiology, Meibergdreef 9, Amsterdam, the Netherlands; Amsterdam Cardiovascular Sciences, Heart Failure and arrhythmias, Amsterdam, the Netherlands
| | - Michael Gollob
- Inherited Arrhythmia and Cardiomyopathy Program, Division of Cardiology, University of Toronto, Toronto ON Canada
| | - Jodie Ingles
- Centre for Population Genomics, Garvan Institute of Medical Research, and UNSW Sydney, Sydney, Australia
| | - James S Ware
- National Heart and Lung Institute, Imperial College London, London, UK
- Royal Brompton and Harefield Hospitals, Guy's and St Thomas' NHS Foundation Trust, London UK
- MRC London Institute of Medical Sciences, Imperial College London, London, UK
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8
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Hiniesto-Iñigo I, Castro-Gonzalez LM, Corradi V, Skarsfeldt MA, Yazdi S, Lundholm S, Nikesjö J, Noskov SY, Bentzen BH, Tieleman DP, Liin SI. Endocannabinoids enhance hK V7.1/KCNE1 channel function and shorten the cardiac action potential and QT interval. EBioMedicine 2023; 89:104459. [PMID: 36796231 PMCID: PMC9958262 DOI: 10.1016/j.ebiom.2023.104459] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Revised: 01/11/2023] [Accepted: 01/18/2023] [Indexed: 02/15/2023] Open
Abstract
BACKGROUND Genotype-positive patients who suffer from the cardiac channelopathy Long QT Syndrome (LQTS) may display a spectrum of clinical phenotypes, with often unknown causes. Therefore, there is a need to identify factors influencing disease severity to move towards an individualized clinical management of LQTS. One possible factor influencing the disease phenotype is the endocannabinoid system, which has emerged as a modulator of cardiovascular function. In this study, we aim to elucidate whether endocannabinoids target the cardiac voltage-gated potassium channel KV7.1/KCNE1, which is the most frequently mutated ion channel in LQTS. METHODS We used two-electrode voltage clamp, molecular dynamics simulations and the E4031 drug-induced LQT2 model of ex-vivo guinea pig hearts. FINDINGS We found a set of endocannabinoids that facilitate channel activation, seen as a shifted voltage-dependence of channel opening and increased overall current amplitude and conductance. We propose that negatively charged endocannabinoids interact with known lipid binding sites at positively charged amino acids on the channel, providing structural insights into why only specific endocannabinoids modulate KV7.1/KCNE1. Using the endocannabinoid ARA-S as a prototype, we show that the effect is not dependent on the KCNE1 subunit or the phosphorylation state of the channel. In guinea pig hearts, ARA-S was found to reverse the E4031-prolonged action potential duration and QT interval. INTERPRETATION We consider the endocannabinoids as an interesting class of hKV7.1/KCNE1 channel modulators with putative protective effects in LQTS contexts. FUNDING ERC (No. 850622), Canadian Institutes of Health Research, Canada Research Chairs and Compute Canada, Swedish National Infrastructure for Computing.
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Affiliation(s)
- Irene Hiniesto-Iñigo
- Department of Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden
| | - Laura M Castro-Gonzalez
- Centre for Molecular Simulation and Department of Biological Sciences, University of Calgary, Calgary, AB, Canada
| | - Valentina Corradi
- Centre for Molecular Simulation and Department of Biological Sciences, University of Calgary, Calgary, AB, Canada
| | - Mark A Skarsfeldt
- Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Samira Yazdi
- Department of Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden
| | - Siri Lundholm
- Department of Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden
| | - Johan Nikesjö
- Department of Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden
| | - Sergei Yu Noskov
- Centre for Molecular Simulation and Department of Biological Sciences, University of Calgary, Calgary, AB, Canada
| | - Bo Hjorth Bentzen
- Department of Biomedical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - D Peter Tieleman
- Centre for Molecular Simulation and Department of Biological Sciences, University of Calgary, Calgary, AB, Canada
| | - Sara I Liin
- Department of Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden.
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9
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O'Neill MJ, Sala L, Denjoy I, Wada Y, Kozek K, Crotti L, Dagradi F, Kotta MC, Spazzolini C, Leenhardt A, Salem JE, Kashiwa A, Ohno S, Tao R, Roden DM, Horie M, Extramiana F, Schwartz PJ, Kroncke BM. Continuous Bayesian variant interpretation accounts for incomplete penetrance among Mendelian cardiac channelopathies. Genet Med 2023; 25:100355. [PMID: 36496179 PMCID: PMC9992222 DOI: 10.1016/j.gim.2022.12.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2022] [Revised: 12/05/2022] [Accepted: 12/05/2022] [Indexed: 12/12/2022] Open
Abstract
PURPOSE The congenital Long QT Syndrome (LQTS) and Brugada Syndrome (BrS) are Mendelian autosomal dominant diseases that frequently precipitate fatal cardiac arrhythmias. Incomplete penetrance is a barrier to clinical management of heterozygotes harboring variants in the major implicated disease genes KCNQ1, KCNH2, and SCN5A. We apply and evaluate a Bayesian penetrance estimation strategy that accounts for this phenomenon. METHODS We generated Bayesian penetrance models for KCNQ1-LQT1 and SCN5A-LQT3 using variant-specific features and clinical data from the literature, international arrhythmia genetic centers, and population controls. We analyzed the distribution of posterior penetrance estimates across 4 genotype-phenotype relationships and compared continuous estimates with ClinVar annotations. Posterior estimates were mapped onto protein structure. RESULTS Bayesian penetrance estimates of KCNQ1-LQT1 and SCN5A-LQT3 are empirically equivalent to 10 and 5 clinically phenotype heterozygotes, respectively. Posterior penetrance estimates were bimodal for KCNQ1-LQT1 and KCNH2-LQT2, with a higher fraction of missense variants with high penetrance among KCNQ1 variants. There was a wide distribution of variant penetrance estimates among identical ClinVar categories. Structural mapping revealed heterogeneity among "hot spot" regions and featured high penetrance estimates for KCNQ1 variants in contact with calmodulin and the S6 domain. CONCLUSIONS Bayesian penetrance estimates provide a continuous framework for variant interpretation.
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Affiliation(s)
- Matthew J O'Neill
- Vanderbilt University School of Medicine, Medical Scientist Training Program, Vanderbilt University, Nashville, TN
| | - Luca Sala
- IRCCS, Istituto Auxologico Italiano, Center for Cardiac Arrhythmias of Genetic Origin and Laboratory of Cardiovascular Genetics, Milano, Italy
| | - Isabelle Denjoy
- Department of Cardiovascular Medicine, Hôpital Bichat, APHP, Université de Paris Cité, Paris, France
| | - Yuko Wada
- Vanderbilt Center for Arrhythmia Research and Therapeutics (VanCART), Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN
| | - Krystian Kozek
- Vanderbilt University School of Medicine, Medical Scientist Training Program, Vanderbilt University, Nashville, TN
| | - Lia Crotti
- IRCCS, Istituto Auxologico Italiano, Center for Cardiac Arrhythmias of Genetic Origin and Laboratory of Cardiovascular Genetics, Milano, Italy
| | - Federica Dagradi
- IRCCS, Istituto Auxologico Italiano, Center for Cardiac Arrhythmias of Genetic Origin and Laboratory of Cardiovascular Genetics, Milano, Italy
| | - Maria-Christina Kotta
- IRCCS, Istituto Auxologico Italiano, Center for Cardiac Arrhythmias of Genetic Origin and Laboratory of Cardiovascular Genetics, Milano, Italy
| | - Carla Spazzolini
- IRCCS, Istituto Auxologico Italiano, Center for Cardiac Arrhythmias of Genetic Origin and Laboratory of Cardiovascular Genetics, Milano, Italy
| | - Antoine Leenhardt
- Department of Cardiovascular Medicine, Hôpital Bichat, APHP, Université de Paris Cité, Paris, France
| | - Joe-Elie Salem
- Department of Cardiovascular Medicine, Hôpital Bichat, APHP, Université de Paris Cité, Paris, France
| | - Asami Kashiwa
- Department of Cardiovascular Medicine, Kyoto University Graduate School of Medicine Kyoto, Japan
| | - Seiko Ohno
- Department of Bioscience and Genetics, National Cerebral and Cardiovascular Center, Osaka, Japan
| | - Ran Tao
- Department of Biostatistics, Vanderbilt University Medical Center, Nashville, TN
| | - Dan M Roden
- Vanderbilt Center for Arrhythmia Research and Therapeutics (VanCART), Departments of Medicine, Pharmacology, and Biomedical Informatics, Vanderbilt University Medical Center, Nashville, TN
| | - Minoru Horie
- Department of Cardiovascular Medicine, Shiga University of Medical Science, Shiga, Japan
| | - Fabrice Extramiana
- Department of Cardiovascular Medicine, Hôpital Bichat, APHP, Université de Paris Cité, Paris, France
| | - Peter J Schwartz
- IRCCS, Istituto Auxologico Italiano, Center for Cardiac Arrhythmias of Genetic Origin and Laboratory of Cardiovascular Genetics, Milano, Italy
| | - Brett M Kroncke
- Vanderbilt Center for Arrhythmia Research and Therapeutics (VanCART), Division of Clinical Pharmacology, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN.
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10
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Phenotypes of Overdiagnosed Long QT Syndrome. J Am Coll Cardiol 2023; 81:477-486. [PMID: 36725176 DOI: 10.1016/j.jacc.2022.11.036] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/19/2022] [Revised: 10/18/2022] [Accepted: 11/03/2022] [Indexed: 02/01/2023]
Abstract
BACKGROUND Long QT syndrome (LQTS) predisposes individuals to arrhythmic syncope or seizure, sudden cardiac arrest, or sudden cardiac death (SCD). Increased physician and public awareness of LQTS-associated warning signs and an increase in electrocardiographic screening programs may contribute to overdiagnosis of LQTS. OBJECTIVES This study sought to identify the diagnostic miscues underlying the continued overdiagnosis of LQTS. METHODS Electronic medical records were reviewed for patients who arrived with an outside diagnosis of LQTS but were dismissed as having normal findings subsequently. Data were abstracted for details on referral, clinical history, and both cardiologic and genetic test results. RESULTS Overall, 290 of 1,841 (16%) patients with original diagnosis of LQTS (174 [60%] female; mean age at first Mayo Clinic evaluation, 22 ± 14 years; mean QTc interval, 427 ± 25 milliseconds) were dismissed as having normal findings. The main cause of LQTS misdiagnosis or overdiagnosis was a prolonged QTc interval secondary to vasovagal syncope (n = 87; 30%), followed by a seemingly positive genetic test result for a variant in 1 of the main LQTS genes (n = 68; 23%) that was ultimately deemed not to be of clinical significance. Furthermore, patients received misdiagnoses because of a positive family history of SCD that was deemed unrelated to LQTS (n = 46; 16%), isolated/transient QT prolongation (n = 44; 15%), or misinterpretation of the QTc interval as a result of inclusion of the U-wave (n = 40, 14%). CONCLUSIONS Knowing the 5 main determinants of discordance between a previously rendered diagnosis of LQTS and full diagnostic reversal or removal (vasovagal syncope, "pseudo"-positive genetic test result in LQTS-causative genes, family history of SCD, transient QT prolongation, and misinterpretation of the QTc interval) increases awareness and provides critical guidance to reduce this burden of overdiagnosed LQTS.
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11
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Lu H, Ding W, Xiao H, Dai M, Xue Y, Jia Z, Guo J, Wu M, Shen B, Zhao R. Association of the P441L KCNQ1 variant with severity of long QT syndrome and risk of cardiac events. Front Cardiovasc Med 2022; 9:922335. [PMID: 36386331 PMCID: PMC9659898 DOI: 10.3389/fcvm.2022.922335] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2022] [Accepted: 09/12/2022] [Indexed: 11/27/2022] Open
Abstract
Dysfunction of potassium voltage-gated channel subfamily Q member 1 (KCNQ1) is a primary cause of long QT syndrome type 1 (LQT1). Here, we report a missense mutation P441L in KCNQ1 C-terminus of a 37-year-old woman with severe LQT1 phenotype. Variant P441L transporting to the plasma membrane and interacting with KCNE1 were both markedly decreased, leading to potassium efflux disorder and eventually LQT1. Mutations between the C-terminal helix A and helix B of KCNQ1 have linked with low cardiac event risk, however, we firstly find variant P441L causing a severe LQT1 phenotype with a high risk of cardiac events.
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Affiliation(s)
- Haoyang Lu
- Department of Cardiovascular Medicine, The First Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Wen Ding
- School of Basic Medical Sciences, Anhui Medical University, Hefei, China
| | - Hui Xiao
- Department of Cardiovascular Medicine, The First Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Manyu Dai
- Department of Cardiovascular Medicine, The First Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Yangcheng Xue
- Department of Cardiovascular Medicine, The First Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Zhuoran Jia
- Department of Cardiovascular Medicine, The First Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Jie Guo
- Department of Cardiovascular Medicine, The First Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Mengzuo Wu
- Department of Cardiovascular Medicine, The First Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Bing Shen
- School of Basic Medical Sciences, Anhui Medical University, Hefei, China
- Bing Shen,
| | - Ren Zhao
- Department of Cardiovascular Medicine, The First Affiliated Hospital of Anhui Medical University, Hefei, China
- *Correspondence: Ren Zhao,
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12
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Chen J, Li H, Guo S, Yang Z, Sun S, Zeng J, Gou H, Chen Y, Wang F, Lin Y, Huang K, Yue H, Ma Y, Lin Y. Whole exome sequencing in Brugada and long QT syndromes revealed novel rare and potential pathogenic mutations related to the dysfunction of the cardiac sodium channel. Orphanet J Rare Dis 2022; 17:394. [PMID: 36303204 PMCID: PMC9615250 DOI: 10.1186/s13023-022-02542-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Accepted: 10/04/2022] [Indexed: 11/21/2022] Open
Abstract
Background Brugada syndrome (Brs) and long QT syndrome (LQTs) are the most observed “inherited primary arrhythmia syndromes” and “channelopathies”, which lead to sudden cardiac death. Methods Detailed clinical information of Brs and LQTs patients was collected. Genomic DNA samples of peripheral blood were conducted for whole-exome sequencing on the Illumina HiSeq 2000 platform. Then, we performed bioinformatics analysis for 200 genes susceptible to arrhythmias and cardiomyopathies. Protein interaction and transcriptomic co-expression were analyzed using the online website and GTEx database.
Results All sixteen cases of Brs and six cases of LQTs were enrolled in the current study. Four Brs carried known pathogenic or likely pathogenic of single-point mutations, including SCN5A p.R661W, SCN5A p.R965C, and KCNH2 p.R692Q. One Brs carried the heterozygous compound mutations of DSG2 p.F531C and SCN5A p.A1374S. Two Brs carried the novel heterozygous truncated mutations (MAF < 0.001) of NEBL (p.R882X) and NPPA (p.R107X), respectively. Except for the indirect interaction between NEBL and SCN5A, NPPA directly interacts with SCN5A. These gene expressions had a specific and significant positive correlation in myocardial tissue, with high degrees of co-expression and synergy. Two Brs carried MYH7 p.E1902Q and MYH6 p.R1820Q, which were predicted as "damaging/possibly damaging" and "damaging/damaging" by Polyphen and SIFT algorithm. Two LQTs elicited the pathogenic single splicing mutation of KCNQ1 (c.922-1G > C). Three LQTs carried a single pathogenic mutation of SCN5A p.R1880H, KCNH2 p.D161N, and KCNQ1 p.R243S, respectively. One patient of LQTs carried a frameshift mutation of KCNH2 p. A188Gfs*143. Conclusions The truncated mutations of NEBL (p.R882X) and NPPA (p.R107X) may induce Brugada syndrome by abnormally affecting cardiac sodium channel. SCN5A (p.R661W, p.R965C and p.A1374S) and KCNH2 (p.R692Q) may cause Brugada syndrome, while SCN5A (p.R1880H), KCNQ1 (c.922-1G > C and p.R243S) and KCNH2 (p.D161N and p.A188Gfs*143) may lead to long QT syndrome.
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Affiliation(s)
- Jia Chen
- The First Dongguan Affiliated Hospital, Guangdong Medical University, Dongguan, 523710, Guangdong Province, China.,The Second Department of Cardiology, Department of Obstetrics and Gynecology, The Second People's Hospital of Guangdong Province, Guangzhou, 510310, Guangdong Province, China
| | - Hong Li
- The First Dongguan Affiliated Hospital, Guangdong Medical University, Dongguan, 523710, Guangdong Province, China.,The University of Hong Kong-Shenzhen Hospital, Shenzhen, 518048, Guangdong Province, China
| | - Sicheng Guo
- The First Dongguan Affiliated Hospital, Guangdong Medical University, Dongguan, 523710, Guangdong Province, China.,College of Plant Protection, Hunan Agricultural University, Changsha, 410128, Hunan Province, China
| | - Zhe Yang
- The First Dongguan Affiliated Hospital, Guangdong Medical University, Dongguan, 523710, Guangdong Province, China.,Department of Endocrinology and Metabolism, Zhuhai Hospital Affiliated to Jinan University, Zhuhai, 519000, Guangdong Province, China
| | - Shaoping Sun
- The First Dongguan Affiliated Hospital, Guangdong Medical University, Dongguan, 523710, Guangdong Province, China
| | - JunJie Zeng
- The First Dongguan Affiliated Hospital, Guangdong Medical University, Dongguan, 523710, Guangdong Province, China
| | - Hongjuan Gou
- The First Dongguan Affiliated Hospital, Guangdong Medical University, Dongguan, 523710, Guangdong Province, China
| | - Yechang Chen
- The First Dongguan Affiliated Hospital, Guangdong Medical University, Dongguan, 523710, Guangdong Province, China
| | - Feng Wang
- Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangdong Geriatrics Institute, Guangdong Cardiovascular Institute, Guangzhou, 510080, Guangdong Province, China
| | - Yanping Lin
- The Second Department of Cardiology, Department of Obstetrics and Gynecology, The Second People's Hospital of Guangdong Province, Guangzhou, 510310, Guangdong Province, China
| | - Kun Huang
- The Second Department of Cardiology, Department of Obstetrics and Gynecology, The Second People's Hospital of Guangdong Province, Guangzhou, 510310, Guangdong Province, China
| | - Hong Yue
- The First Dongguan Affiliated Hospital, Guangdong Medical University, Dongguan, 523710, Guangdong Province, China.
| | - Yuting Ma
- The First Dongguan Affiliated Hospital, Guangdong Medical University, Dongguan, 523710, Guangdong Province, China. .,College of Life Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China.
| | - Yubi Lin
- The First Dongguan Affiliated Hospital, Guangdong Medical University, Dongguan, 523710, Guangdong Province, China. .,Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangdong Geriatrics Institute, Guangdong Cardiovascular Institute, Guangzhou, 510080, Guangdong Province, China.
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13
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Eosinophilic Infiltration of the Sino-Atrial Node in Sudden Cardiac Death Caused by Long QT Syndrome. Int J Mol Sci 2022; 23:ijms231911666. [PMID: 36232963 PMCID: PMC9569895 DOI: 10.3390/ijms231911666] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Revised: 09/25/2022] [Accepted: 09/28/2022] [Indexed: 11/09/2022] Open
Abstract
Sudden death is defined as the unexpected death of a healthy person that occurs within the first hour of the onset of symptoms or within 24 h of the victim being last seen alive. In some of these cases, rare deleterious variants of genes associated with inherited cardiac disorders can provide a highly probable explanation for the fatal event. We report the case of a 21-year-old obese woman who lost consciousness suddenly in a public place and was pronounced dead after hospital admission. Clinical autopsy showed an inconclusive gross examination, while in the histopathological analysis an eosinophilic inflammatory focus and interstitial fibrosis in the sino-atrial node were found. Molecular autopsy revealed an intronic variant in the KCNQ1 gene (c.683 + 5G > A), classified as likely pathogenic for long QT syndrome according to the guidelines provided by the American College of Medical Genetics and Genomics. Therefore, there were many anomalies that could have played a role in the causation of the sudden death, such as the extreme obesity, the cardiac anomalies and the KNCQ1 variant. This case depicts the difficult interpretation of rare cardiac structural abnormalities in subjects carrying rare variants responsible for inherited arrhythmic disorders and the challenge for the forensic pathologist to make causal inferences in the determinism of the unexpected decease.
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14
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Wu X, Li Y, Hong L. Effects of Mexiletine on a Race-specific Mutation in Nav1.5 Associated With Long QT Syndrome. Front Physiol 2022; 13:904664. [PMID: 35864896 PMCID: PMC9294368 DOI: 10.3389/fphys.2022.904664] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2022] [Accepted: 06/14/2022] [Indexed: 11/13/2022] Open
Abstract
The voltage-gated sodium channel Nav1.5 plays an essential role in the generation and propagation of action potential in cardiomyocytes. Mutations in Nav1.5 have been associated with LQT syndrome, Brugada syndrome, and sudden arrhythmia death syndrome. Genetic studies showed that Nav1.5 mutations vary across race-ethnic groups. Here we investigated an Asian-specific mutation Nav1.5-P1090L associated with LQT syndrome. We found that Nav1.5-P1090L mutation perturbed the sodium channel function. It altered the gating process of the channel and exhibited an enhanced window current. Treatment with mexiletine reversed the depolarization shift of the steady-state inactivation produced by P1090L. Mexiletine also modified the recovery from steady-state inactivation and the development of inactivation of P1090L. It rescued the dysfunctional inactivation of P1090L and reduced the P1090L channel’s availability.
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Affiliation(s)
- Xin Wu
- Department of Medicine, University of Illinois at Chicago, Chicago, IL, United States
| | - Yawei Li
- Department of Preventive Medicine, Northwestern University, Chicago, IL, United States
| | - Liang Hong
- Department of Medicine, University of Illinois at Chicago, Chicago, IL, United States
- *Correspondence: Liang Hong,
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15
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Kekenes-Huskey PM, Burgess DE, Sun B, Bartos DC, Rozmus ER, Anderson CL, January CT, Eckhardt LL, Delisle BP. Mutation-Specific Differences in Kv7.1 ( KCNQ1) and Kv11.1 ( KCNH2) Channel Dysfunction and Long QT Syndrome Phenotypes. Int J Mol Sci 2022; 23:7389. [PMID: 35806392 PMCID: PMC9266926 DOI: 10.3390/ijms23137389] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2022] [Revised: 06/22/2022] [Accepted: 06/24/2022] [Indexed: 11/16/2022] Open
Abstract
The electrocardiogram (ECG) empowered clinician scientists to measure the electrical activity of the heart noninvasively to identify arrhythmias and heart disease. Shortly after the standardization of the 12-lead ECG for the diagnosis of heart disease, several families with autosomal recessive (Jervell and Lange-Nielsen Syndrome) and dominant (Romano-Ward Syndrome) forms of long QT syndrome (LQTS) were identified. An abnormally long heart rate-corrected QT-interval was established as a biomarker for the risk of sudden cardiac death. Since then, the International LQTS Registry was established; a phenotypic scoring system to identify LQTS patients was developed; the major genes that associate with typical forms of LQTS were identified; and guidelines for the successful management of patients advanced. In this review, we discuss the molecular and cellular mechanisms for LQTS associated with missense variants in KCNQ1 (LQT1) and KCNH2 (LQT2). We move beyond the "benign" to a "pathogenic" binary classification scheme for different KCNQ1 and KCNH2 missense variants and discuss gene- and mutation-specific differences in K+ channel dysfunction, which can predispose people to distinct clinical phenotypes (e.g., concealed, pleiotropic, severe, etc.). We conclude by discussing the emerging computational structural modeling strategies that will distinguish between dysfunctional subtypes of KCNQ1 and KCNH2 variants, with the goal of realizing a layered precision medicine approach focused on individuals.
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Affiliation(s)
- Peter M. Kekenes-Huskey
- Department of Cell and Molecular Physiology, Stritch School of Medicine, Loyola University Chicago, Maywood, IL 60153, USA
| | - Don E. Burgess
- Department of Physiology, College of Medicine, University of Kentucky, Lexington, KY 40536, USA; (D.E.B.); (E.R.R.)
| | - Bin Sun
- Department of Pharmacology, Harbin Medical University, Harbin 150081, China;
| | | | - Ezekiel R. Rozmus
- Department of Physiology, College of Medicine, University of Kentucky, Lexington, KY 40536, USA; (D.E.B.); (E.R.R.)
| | - Corey L. Anderson
- Cellular and Molecular Arrythmias Program, Division of Cardiovascular Medicine, Department of Medicine, University of Wisconsin-Madison, Madison, WI 53705, USA; (C.L.A.); (C.T.J.); (L.L.E.)
| | - Craig T. January
- Cellular and Molecular Arrythmias Program, Division of Cardiovascular Medicine, Department of Medicine, University of Wisconsin-Madison, Madison, WI 53705, USA; (C.L.A.); (C.T.J.); (L.L.E.)
| | - Lee L. Eckhardt
- Cellular and Molecular Arrythmias Program, Division of Cardiovascular Medicine, Department of Medicine, University of Wisconsin-Madison, Madison, WI 53705, USA; (C.L.A.); (C.T.J.); (L.L.E.)
| | - Brian P. Delisle
- Department of Physiology, College of Medicine, University of Kentucky, Lexington, KY 40536, USA; (D.E.B.); (E.R.R.)
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16
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Song Y, Guo T, Jiang Y, Zhu M, Wang H, Lu W, Jiang M, Qi M, Lan F, Cui M. KCNQ1-deficient and KCNQ1-mutant human embryonic stem cell-derived cardiomyocytes for modeling QT prolongation. Stem Cell Res Ther 2022; 13:287. [PMID: 35765105 PMCID: PMC9241307 DOI: 10.1186/s13287-022-02964-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Accepted: 03/20/2022] [Indexed: 11/10/2022] Open
Abstract
Background The slowly activated delayed rectifier potassium current (IKs) mediated by the KCNQ1 gene is one of the main currents involved in repolarization. KCNQ1 mutation can result in long-QT syndrome type 1 (LQT1). IKs does not participate in repolarization in mice; thus, no good model is currently available for research on the mechanism of and drug screening for LQT1. In this study, we established a KCNQ1-deficient human cardiomyocyte (CM) model and performed a series of microelectrode array (MEA) detection experiments on KCNQ1-mutant CMs constructed in other studies to explore the pathogenic mechanism of KCNQ1 deletion and mutation and perform drug screening. Method KCNQ1 was knocked out in human embryonic stem cell (hESC) H9 line using the CRISPR/cas9 system. KCNQ1-deficient and KCNQ1-mutant hESCs were differentiated into CMs through a chemically defined differentiation protocol. Subsequently, high-throughput MEA analysis and drug intervention were performed to determine the electrophysiological characteristics of KCNQ1-deficient and KCNQ1-mutant CMs. Results During high-throughput MEA analysis, the electric field potential and action potential durations in KCNQ1-deficient CMs were significantly longer than those in wild-type CMs. KCNQ1-deficient CMs also showed an irregular rhythm. Furthermore, KCNQ1-deficient and KCNQ1-mutant CMs showed different responses to different drug treatments, which reflected the differences in their pathogenic mechanisms. Conclusion We established a human CM model with KCNQ1 deficiency showing a prolonged QT interval and an irregular heart rhythm. Further, we used various drugs to treat KCNQ1-deficient and KCNQ1-mutant CMs, and the three models showed different responses to these drugs. These models can be used as important tools for studying the different pathogenic mechanisms of KCNQ1 mutation and the relationship between the genotype and phenotype of KCNQ1, thereby facilitating drug development. Supplementary Information The online version contains supplementary material available at 10.1186/s13287-022-02964-3.
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Affiliation(s)
- Yuanxiu Song
- Department of Cardiology, Peking University Third Hospital, 49 Huayuan North Road, Haidian District, Beijing, 100191, China
| | - Tianwei Guo
- Beijing Lab for Cardiovascular Precision Medicine, Anzhen Hospital, Capital Medical University, Beijing, 100029, China
| | - Youxu Jiang
- Department of Cardiology, The Second Affiliated Hospital of Zhengzhou University, Jingba Road, Zhengzhou, 450053, China
| | - Min Zhu
- State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100037, China
| | - Hongyue Wang
- State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100037, China
| | - Wenjing Lu
- Shenzhen Key Laboratory of Cardiovascular Disease, Fuwai Hospital Chinese Academy of Medical Sciences, Chinese Academy of Medical Sciences and Peking Union Medical College, Shenzhen, 518057, China
| | - Mengqi Jiang
- Department of Cell Biology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, 100191, China
| | - Man Qi
- State Key Laboratory of Cardiovascular Disease, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100037, China
| | - Feng Lan
- Shenzhen Key Laboratory of Cardiovascular Disease, Fuwai Hospital Chinese Academy of Medical Sciences, Chinese Academy of Medical Sciences and Peking Union Medical College, Shenzhen, 518057, China.
| | - Ming Cui
- Department of Cardiology, Peking University Third Hospital, 49 Huayuan North Road, Haidian District, Beijing, 100191, China.
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17
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Lorca R, Junco-Vicente A, Pérez-Pérez A, Pascual I, Persia-Paulino YR, González-Urbistondo F, Cuesta-Llavona E, Fernández-Barrio BC, Morís C, Rubín JM, Coto E, Gómez J, Reguero JJR. KCNH2 p.Gly262AlafsTer98: A New Threatening Variant Associated with Long QT Syndrome in a Spanish Cohort. Life (Basel) 2022; 12:life12040556. [PMID: 35455047 PMCID: PMC9024605 DOI: 10.3390/life12040556] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Revised: 03/27/2022] [Accepted: 04/05/2022] [Indexed: 11/16/2022] Open
Abstract
Long QT syndrome (LQTS) is an inherited (autosomal dominant) channelopathy associated with susceptibility to ventricular arrhythmias due to malfunction of ion channels in cardiomyocytes, that could lead to sudden death (SD). Most pathogenic variants are in the main 3 genes: KCNQ1 (LQT1), KCNH2 (LQT2) and SCN5A (LQT3). Efforts to improve the understanding of the genotype-phenotype relationship are essential to improve the medical clinical practice. In this study, we identified all index patients referred for NGS genetic sequencing due to LQTS, in a Spanish cohort, who were carriers of a new pathogenic variant (KCNH2 p.Gly262AlafsTer98). Genetic and clinical family screening was performed in order to describe its phenotypic characteristics. We identified 22 relatives of Romani ethnicity, who were carriers of the variant. Penetrance reached a 100% and adherence to medical treatment was low. There was a high rate of clinical events, particularly arrhythmic events and SD (1 in every 4 patients presented syncope, 1 presented an aborted SD, 2 obligated carriers suffered SD before the age of 40 and 4 out of 6 carriers of an implantable cardioverter-defibrillator (ICD) had appropriate ICD therapies. Correct adherence to medical treatment in all carriers should be specially encouraged in this population. ICD implantation decision in non-compliant patients, and refusing left cardiac sympathetic denervation, should be carefully outweighed.
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Affiliation(s)
- Rebeca Lorca
- Unidad de Referencia de Cardiopatías Familiares-HUCA, Área del Corazón y Departamento de Genética Molecular, Hospital Universitario Central de Asturias, 33011 Oviedo, Spain; (R.L.); (E.C.-L.); (C.M.); (J.M.R.); (E.C.); (J.G.); (J.J.R.R.)
- Heart Area, Hospital Universitario Central de Asturias, 33011 Oviedo, Spain; (A.J.-V.); (Y.R.P.-P.); (F.G.-U.)
- Instituto de Investigación Sanitaria del Principado de Asturias (ISPA), 33011 Oviedo, Spain
| | - Alejandro Junco-Vicente
- Heart Area, Hospital Universitario Central de Asturias, 33011 Oviedo, Spain; (A.J.-V.); (Y.R.P.-P.); (F.G.-U.)
| | - Alicia Pérez-Pérez
- Pediatric Area, Hospital Universitario Central de Asturias, 33011 Oviedo, Spain; (A.P.-P.); (B.C.F.-B.)
| | - Isaac Pascual
- Heart Area, Hospital Universitario Central de Asturias, 33011 Oviedo, Spain; (A.J.-V.); (Y.R.P.-P.); (F.G.-U.)
- Instituto de Investigación Sanitaria del Principado de Asturias (ISPA), 33011 Oviedo, Spain
- Correspondence:
| | - Yvan Rafael Persia-Paulino
- Heart Area, Hospital Universitario Central de Asturias, 33011 Oviedo, Spain; (A.J.-V.); (Y.R.P.-P.); (F.G.-U.)
| | | | - Elías Cuesta-Llavona
- Unidad de Referencia de Cardiopatías Familiares-HUCA, Área del Corazón y Departamento de Genética Molecular, Hospital Universitario Central de Asturias, 33011 Oviedo, Spain; (R.L.); (E.C.-L.); (C.M.); (J.M.R.); (E.C.); (J.G.); (J.J.R.R.)
- Instituto de Investigación Sanitaria del Principado de Asturias (ISPA), 33011 Oviedo, Spain
| | | | - César Morís
- Unidad de Referencia de Cardiopatías Familiares-HUCA, Área del Corazón y Departamento de Genética Molecular, Hospital Universitario Central de Asturias, 33011 Oviedo, Spain; (R.L.); (E.C.-L.); (C.M.); (J.M.R.); (E.C.); (J.G.); (J.J.R.R.)
- Heart Area, Hospital Universitario Central de Asturias, 33011 Oviedo, Spain; (A.J.-V.); (Y.R.P.-P.); (F.G.-U.)
- Instituto de Investigación Sanitaria del Principado de Asturias (ISPA), 33011 Oviedo, Spain
| | - José Manuel Rubín
- Unidad de Referencia de Cardiopatías Familiares-HUCA, Área del Corazón y Departamento de Genética Molecular, Hospital Universitario Central de Asturias, 33011 Oviedo, Spain; (R.L.); (E.C.-L.); (C.M.); (J.M.R.); (E.C.); (J.G.); (J.J.R.R.)
- Heart Area, Hospital Universitario Central de Asturias, 33011 Oviedo, Spain; (A.J.-V.); (Y.R.P.-P.); (F.G.-U.)
- Instituto de Investigación Sanitaria del Principado de Asturias (ISPA), 33011 Oviedo, Spain
| | - Eliecer Coto
- Unidad de Referencia de Cardiopatías Familiares-HUCA, Área del Corazón y Departamento de Genética Molecular, Hospital Universitario Central de Asturias, 33011 Oviedo, Spain; (R.L.); (E.C.-L.); (C.M.); (J.M.R.); (E.C.); (J.G.); (J.J.R.R.)
- Instituto de Investigación Sanitaria del Principado de Asturias (ISPA), 33011 Oviedo, Spain
| | - Juan Gómez
- Unidad de Referencia de Cardiopatías Familiares-HUCA, Área del Corazón y Departamento de Genética Molecular, Hospital Universitario Central de Asturias, 33011 Oviedo, Spain; (R.L.); (E.C.-L.); (C.M.); (J.M.R.); (E.C.); (J.G.); (J.J.R.R.)
- Instituto de Investigación Sanitaria del Principado de Asturias (ISPA), 33011 Oviedo, Spain
- CIBER-Enfermedades Respiratorias, 28029 Madrid, Spain
| | - José Julián Rodríguez Reguero
- Unidad de Referencia de Cardiopatías Familiares-HUCA, Área del Corazón y Departamento de Genética Molecular, Hospital Universitario Central de Asturias, 33011 Oviedo, Spain; (R.L.); (E.C.-L.); (C.M.); (J.M.R.); (E.C.); (J.G.); (J.J.R.R.)
- Heart Area, Hospital Universitario Central de Asturias, 33011 Oviedo, Spain; (A.J.-V.); (Y.R.P.-P.); (F.G.-U.)
- Instituto de Investigación Sanitaria del Principado de Asturias (ISPA), 33011 Oviedo, Spain
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18
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Bains S, Dotzler SM, Krijger C, Giudicessi JR, Ye D, Bikker H, Rohatgi RK, Tester DJ, Bos JM, Wilde AAM, Ackerman MJ. A phenotype-enhanced variant classification framework to decrease the burden of missense variants of uncertain significance in type 1 long QT syndrome. Heart Rhythm 2021; 19:435-442. [PMID: 34798354 DOI: 10.1016/j.hrthm.2021.11.017] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Revised: 11/10/2021] [Accepted: 11/11/2021] [Indexed: 12/16/2022]
Abstract
BACKGROUND Pathogenic/likely pathogenic (P/LP) variants in the KCNQ1-encoded Kv7.1 potassium channel cause type 1 long QT syndrome (LQT1). Despite the revamped 2015 American College of Medical Genetics (ACMG) variant interpretation guidelines, the burden of KCNQ1 variants of uncertain significance (VUS) in patients with LQTS remains ∼30%. OBJECTIVE The purpose of this study was to determine whether a phenotype-enhanced (PE) variant classification approach could reduce the VUS burden in LQTS genetic testing. METHODS Retrospective analysis was performed on 79 KCNQ1 missense variants in 356 patients from Mayo Clinic and an independent cohort of 42 variants in 225 patients from Amsterdam University Medical Center (UMC). Each variant was classified initially using the ACMG guidelines and then readjudicated using a PE-ACMG framework that incorporated the LQTS clinical diagnostic Schwartz score plus 4 "LQT1-defining features": broad-based/slow upstroke T waves, syncope/seizure during exertion, swimming-associated events, and a maladaptive LQT1 treadmill stress test. RESULTS According to the ACMG guidelines, Mayo Clinic variants were classified as follows: 17 of 79 P variants (22%), 34 of 79 LP variants (43%), and 28 of 79 VUS (35%). Similarly, for Amsterdam UMC, the variant distribution was 9 of 42 P variants (22%), 14 of 42 LP variants (33%), and 19 of 42 variants VUS (45%). After PE-ACMG readjudication, the total VUS burden decreased significantly from 28 (35%) to 13 (16%) (P = .0007) for Mayo Clinic and from 19 (45%) to 12 (29%) (P = .02) for Amsterdam UMC. CONCLUSION Phenotype-guided variant adjudication decreased significantly the VUS burden of LQT1 case-derived KCNQ1 missense variants in 2 independent cohorts. This study demonstrates the value of incorporating LQT1-specific phenotype/clinical data to aid in the interpretation of KCNQ1 missense variants identified during genetic testing for LQTS.
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Affiliation(s)
- Sahej Bains
- Medical Scientist Training Program, Mayo Clinic, Rochester, Minnesota; Department of Molecular Pharmacology and Experimental Therapeutics, Windland Smith Rice Sudden Death Genomics Laboratory, Mayo Clinic, Rochester, Minnesota
| | - Steven M Dotzler
- Medical Scientist Training Program, Mayo Clinic, Rochester, Minnesota; Department of Molecular Pharmacology and Experimental Therapeutics, Windland Smith Rice Sudden Death Genomics Laboratory, Mayo Clinic, Rochester, Minnesota
| | - Christian Krijger
- Department of Experimental Cardiology, Amsterdam University Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - John R Giudicessi
- Department of Cardiovascular Medicine, Division of Heart Rhythm Services, Windland Smith Rice Genetic Heart Rhythm Clinic, Mayo Clinic, Rochester, Minnesota
| | - Dan Ye
- Department of Molecular Pharmacology and Experimental Therapeutics, Windland Smith Rice Sudden Death Genomics Laboratory, Mayo Clinic, Rochester, Minnesota
| | - Hennie Bikker
- Department of Human Genetics, University of Amsterdam, Amsterdam University Medical Center, Amsterdam, The Netherlands
| | - Ram K Rohatgi
- Department of Pediatric and Adolescent Medicine (Division of Pediatric Cardiology), Mayo Clinic, Rochester, Minnesota
| | - David J Tester
- Department of Molecular Pharmacology and Experimental Therapeutics, Windland Smith Rice Sudden Death Genomics Laboratory, Mayo Clinic, Rochester, Minnesota; Department of Cardiovascular Medicine, Division of Heart Rhythm Services, Windland Smith Rice Genetic Heart Rhythm Clinic, Mayo Clinic, Rochester, Minnesota; Department of Pediatric and Adolescent Medicine (Division of Pediatric Cardiology), Mayo Clinic, Rochester, Minnesota
| | - J Martijn Bos
- Department of Molecular Pharmacology and Experimental Therapeutics, Windland Smith Rice Sudden Death Genomics Laboratory, Mayo Clinic, Rochester, Minnesota; Department of Cardiovascular Medicine, Division of Heart Rhythm Services, Windland Smith Rice Genetic Heart Rhythm Clinic, Mayo Clinic, Rochester, Minnesota; Department of Pediatric and Adolescent Medicine (Division of Pediatric Cardiology), Mayo Clinic, Rochester, Minnesota
| | - Arthur A M Wilde
- Department of Experimental Cardiology, Amsterdam University Medical Center, University of Amsterdam, Amsterdam, The Netherlands; Department of Cardiology, Amsterdam University Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Michael J Ackerman
- Department of Molecular Pharmacology and Experimental Therapeutics, Windland Smith Rice Sudden Death Genomics Laboratory, Mayo Clinic, Rochester, Minnesota; Department of Cardiovascular Medicine, Division of Heart Rhythm Services, Windland Smith Rice Genetic Heart Rhythm Clinic, Mayo Clinic, Rochester, Minnesota; Department of Pediatric and Adolescent Medicine (Division of Pediatric Cardiology), Mayo Clinic, Rochester, Minnesota.
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19
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Oliveira‐Mendes B, Feliciangeli S, Ménard M, Chatelain F, Alameh M, Montnach J, Nicolas S, Ollivier B, Barc J, Baró I, Schott J, Probst V, Kyndt F, Denjoy I, Lesage F, Loussouarn G, De Waard M. A standardised hERG phenotyping pipeline to evaluate KCNH2 genetic variant pathogenicity. Clin Transl Med 2021; 11:e609. [PMID: 34841674 PMCID: PMC8609418 DOI: 10.1002/ctm2.609] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Revised: 09/22/2021] [Accepted: 09/28/2021] [Indexed: 12/19/2022] Open
Abstract
BACKGROUND AND AIMS Mutations in KCNH2 cause long or short QT syndromes (LQTS or SQTS) predisposing to life-threatening arrhythmias. Over 1000 hERG variants have been described by clinicians, but most remain to be characterised. The objective is to standardise and accelerate the phenotyping process to contribute to clinician diagnosis and patient counselling. In silico evaluation was also included to characterise the structural impact of the variants. METHODS We selected 11 variants from known LQTS patients and two variants for which diagnosis was problematic. Using the Gibson assembly strategy, we efficiently introduced mutations in hERG cDNA despite GC-rich sequences. A pH-sensitive fluorescent tag was fused to hERG for efficient evaluation of channel trafficking. An optimised 35-s patch-clamp protocol was developed to evaluate hERG channel activity in transfected cells. R software was used to speed up analyses. RESULTS In the present work, we observed a good correlation between cell surface expression, assessed by the pH-sensitive tag, and current densities. Also, we showed that the new biophysical protocol allows a significant gain of time in recording ion channel properties and provides extensive information on WT and variant channel biophysical parameters, that can all be recapitulated in a single parameter defined herein as the repolarisation power. The impacts of the variants on channel structure were also reported where structural information was available. These three readouts (trafficking, repolarisation power and structural impact) define three pathogenicity indexes that may help clinical diagnosis. CONCLUSIONS Fast-track characterisation of KCNH2 genetic variants shows its relevance to discriminate mutants that affect hERG channel activity from variants with undetectable effects. It also helped the diagnosis of two new variants. This information is meant to fill a patient database, as a basis for personalised medicine. The next steps will be to further accelerate the process using an automated patch-clamp system.
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Affiliation(s)
| | - Sylvain Feliciangeli
- Labex ICST, Université Côte d'Azur, INSERMCentre National de la Recherche Scientifique, Institut de Pharmacologie Moléculaire et CellulaireValbonneFrance
| | - Mélissa Ménard
- l'Institut du ThoraxInserm UMR 1087/CNRS UMR 6291NantesFrance
| | - Frank Chatelain
- Labex ICST, Université Côte d'Azur, INSERMCentre National de la Recherche Scientifique, Institut de Pharmacologie Moléculaire et CellulaireValbonneFrance
| | - Malak Alameh
- l'Institut du ThoraxInserm UMR 1087/CNRS UMR 6291NantesFrance
| | - Jérôme Montnach
- l'Institut du ThoraxInserm UMR 1087/CNRS UMR 6291NantesFrance
| | | | | | - Julien Barc
- l'Institut du ThoraxInserm UMR 1087/CNRS UMR 6291NantesFrance
| | - Isabelle Baró
- l'Institut du ThoraxInserm UMR 1087/CNRS UMR 6291NantesFrance
| | | | - Vincent Probst
- CHU Nantes, l'Institut du Thorax, INSERM, CNRSUNIV NantesNantesFrance
| | - Florence Kyndt
- CHU Nantes, l'Institut du Thorax, INSERM, CNRSUNIV NantesNantesFrance
| | - Isabelle Denjoy
- Service de Cardiologie et CNMR Maladies Cardiaques Héréditaires RaresHôpital BichatParisFrance
| | - Florian Lesage
- Labex ICST, Université Côte d'Azur, INSERMCentre National de la Recherche Scientifique, Institut de Pharmacologie Moléculaire et CellulaireValbonneFrance
| | | | - Michel De Waard
- l'Institut du ThoraxInserm UMR 1087/CNRS UMR 6291NantesFrance
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20
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Schwartz PJ, Moreno C, Kotta MC, Pedrazzini M, Crotti L, Dagradi F, Castelletti S, Haugaa KH, Denjoy I, Shkolnikova MA, Brink PA, Heradien MJ, Seyen SRM, Spätjens RLHMG, Spazzolini C, Volders PGA. Mutation location and IKs regulation in the arrhythmic risk of long QT syndrome type 1: the importance of the KCNQ1 S6 region. Eur Heart J 2021; 42:4743-4755. [PMID: 34505893 DOI: 10.1093/eurheartj/ehab582] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/26/2021] [Revised: 07/02/2021] [Accepted: 09/02/2021] [Indexed: 11/13/2022] Open
Abstract
AIMS Mutation type, location, dominant-negative IKs reduction, and possibly loss of cyclic adenosine monophosphate (cAMP)-dependent IKs stimulation via protein kinase A (PKA) influence the clinical severity of long QT syndrome type 1 (LQT1). Given the malignancy of KCNQ1-p.A341V, we assessed whether mutations neighbouring p.A341V in the S6 channel segment could also increase arrhythmic risk. METHODS AND RESULTS Clinical and genetic data were obtained from 1316 LQT1 patients [450 families, 166 unique KCNQ1 mutations, including 277 p.A341V-positive subjects, 139 patients with p.A341-neighbouring mutations (91 missense, 48 non-missense), and 900 other LQT1 subjects]. A first cardiac event represented the primary endpoint. S6 segment missense variant characteristics, particularly cAMP stimulation responses, were analysed by cellular electrophysiology. p.A341-neighbouring mutation carriers had a QTc shorter than p.A341V carriers (477 ± 33 vs. 490 ± 44 ms) but longer than the remaining LQT1 patient population (467 ± 41 ms) (P < 0.05 for both). Similarly, the frequency of symptomatic subjects in the p.A341-neighbouring subgroup was intermediate between the other two groups (43% vs. 73% vs. 20%; P < 0.001). These differences in clinical severity can be explained, for p.A341V vs. p.A341-neighbouring mutations, by the p.A341V-specific impairment of IKs regulation. The differences between the p.A341-neighbouring subgroup and the rest of LQT1 mutations may be explained by the functional importance of the S6 segment for channel activation. CONCLUSION KCNQ1 S6 segment mutations surrounding p.A341 increase arrhythmic risk. p.A341V-specific loss of PKA-dependent IKs enhancement correlates with its phenotypic severity. Cellular studies providing further insights into IKs-channel regulation and knowledge of structure-function relationships could improve risk stratification. These findings impact on clinical management.
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Affiliation(s)
- Peter J Schwartz
- Istituto Auxologico Italiano, IRCCS, Center for Cardiac Arrhythmias of Genetic Origin, Via Pier Lombardo, 22, 20135 Milan, Italy.,Istituto Auxologico Italiano, IRCCS, Laboratory of Cardiovascular Genetics, via Zucchi 18, 20095 Cusano Milanino, MI, Italy
| | - Cristina Moreno
- Department of Cardiology, CARIM, Maastricht University Medical Center, PO Box 5800, 6202 Maastricht, The Netherlands.,Molecular Neurophysiology Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, 35 Convent Dr., Bethesda, MD 20892-3701, USA
| | - Maria-Christina Kotta
- Istituto Auxologico Italiano, IRCCS, Laboratory of Cardiovascular Genetics, via Zucchi 18, 20095 Cusano Milanino, MI, Italy
| | - Matteo Pedrazzini
- Istituto Auxologico Italiano, IRCCS, Laboratory of Cardiovascular Genetics, via Zucchi 18, 20095 Cusano Milanino, MI, Italy
| | - Lia Crotti
- Istituto Auxologico Italiano, IRCCS, Center for Cardiac Arrhythmias of Genetic Origin, Via Pier Lombardo, 22, 20135 Milan, Italy.,Istituto Auxologico Italiano, IRCCS, Laboratory of Cardiovascular Genetics, via Zucchi 18, 20095 Cusano Milanino, MI, Italy.,Department of Cardiovascular, Neural and Metabolic Sciences, Istituto Auxologico Italiano, IRCCS, San Luca Hospital, Piazzale Brescia 20, 20149 Milan, Italy.,Department of Medicine and Surgery, University of Milano-Bicocca, Piazza dell'Ateneo Nuovo, 1, 20126 Milano, Italy
| | - Federica Dagradi
- Istituto Auxologico Italiano, IRCCS, Center for Cardiac Arrhythmias of Genetic Origin, Via Pier Lombardo, 22, 20135 Milan, Italy
| | - Silvia Castelletti
- Istituto Auxologico Italiano, IRCCS, Center for Cardiac Arrhythmias of Genetic Origin, Via Pier Lombardo, 22, 20135 Milan, Italy
| | - Kristina H Haugaa
- ProCardio center for innovation, Department of Cardiology, Oslo University Hospital, Postboks 4950 Nydalen, 0424 Oslo, Norway.,University of Oslo, Postboks 1171, Blindern 0318 Oslo, Norway
| | - Isabelle Denjoy
- Centre de Référence Maladies Cardiaques Héréditaires, Filière Cardiogen, Département de Rythmologie, Groupe Hospitalier Bichat-Claude Bernard, 46 Rue Henri -Huchard, 75877 PARIS Cedex 18, France
| | - Maria A Shkolnikova
- Pirogov Russian National Research Medical University, Research and Clinical Institute for Pediatrics named after Academician Yuri Veltischev, Centre for Cardiac Arrhythmia, Taldomskaya 2, 125412 Moscow, Russian Federation
| | - Paul A Brink
- Department of Internal Medicine, Stellenbosch University, Tygerberg 7505, South Africa
| | - Marshall J Heradien
- Department of Internal Medicine, Stellenbosch University, Tygerberg 7505, South Africa
| | - Sandrine R M Seyen
- Department of Cardiology, CARIM, Maastricht University Medical Center, PO Box 5800, 6202 Maastricht, The Netherlands
| | - Roel L H M G Spätjens
- Department of Cardiology, CARIM, Maastricht University Medical Center, PO Box 5800, 6202 Maastricht, The Netherlands
| | - Carla Spazzolini
- Istituto Auxologico Italiano, IRCCS, Center for Cardiac Arrhythmias of Genetic Origin, Via Pier Lombardo, 22, 20135 Milan, Italy
| | - Paul G A Volders
- Department of Cardiology, CARIM, Maastricht University Medical Center, PO Box 5800, 6202 Maastricht, The Netherlands
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21
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Simons E, Labro A, Saenen J, Nijak A, Sieliwonczyk E, Vandendriessche B, Dąbrowska M, Van Craenenbroeck EM, Schepers D, Van Laer L, Loeys BL, Alaerts M. Molecular autopsy and subsequent functional analysis reveal de novo DSG2 mutation as cause of sudden death. Eur J Med Genet 2021; 64:104322. [PMID: 34438094 DOI: 10.1016/j.ejmg.2021.104322] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Revised: 08/15/2021] [Accepted: 08/22/2021] [Indexed: 11/28/2022]
Abstract
Sudden cardiac death (SCD) is a common cause of death in young adults. In up to 80% of cases a genetic cause is suspected. Next-generation sequencing of candidate genes can reveal the cause of SCD, provide prognostic management, and facilitate pre-symptomatic testing and prevention in relatives. Here we present a proband who experienced SCD in his sleep for which molecular autopsy was performed. We performed a post-mortem genetic analysis of a 49-year-old male who died during sleep after competitive kayaking, using a Cardiomyopathy and Primary Arrhythmia next-generation sequencing panel, each containing 51 candidate genes. Autopsy was not performed. Genetic testing of the proband resulted in missense variants in KCNQ1 (c.1449C > A; p.(Asn483Lys)) and DSG2 (c.2979G > T; p.(Gln993His)), both absent from the gnomAD database. Familial segregation analysis showed de novo occurrence of the DSG2 variant and presence of the KCNQ1 variant in the proband's mother and daughter. KCNQ1 p.(Asn483Lys) was predicted to be pathogenic by MutationTaster. However, none of the KCNQ1 variant carrying family members showed long QTc on ECG or Holter. We further functionally analysed this variant using patch-clamp in a heterologous expression system (Chinese Hamster Ovary (CHO) cells) expressing the KCNQ1 mutant in combination with KCNE1 wild type protein and showed no significant changes in electrophysiological function of Kv7.1. Based on the above evidence, we concluded that the DSG2 p.(Gln993His) variant is the most likely cause of SCD in the presented case, and that there is insufficient evidence that the identified KCNQ1 p.(Asn483Lys) variant would confer risk for SCD in his mother and daughter. Fortunately, the DSG2 variant was not inherited by the proband's two children. This case report indicates the added value of molecular autopsy and the importance of subsequent functional study of variants to inform patients and family members about the risk of variants they might carry.
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Affiliation(s)
- Eline Simons
- Cardiogenetics Research Group, Center of Medical Genetics, University of Antwerp and Antwerp University Hospital, Antwerp, Belgium
| | - Alain Labro
- Laboratory for Molecular, Cellular and Network Excitability, University of Antwerp, Antwerp, Belgium; Department of Basic and Applied Medical Sciences, Faculty of Medicine and Health Sciences, Ghent University, Ghent, Belgium
| | - Johan Saenen
- Department of Cardiology, Antwerp University Hospital, Antwerp, Belgium
| | - Aleksandra Nijak
- Cardiogenetics Research Group, Center of Medical Genetics, University of Antwerp and Antwerp University Hospital, Antwerp, Belgium
| | - Ewa Sieliwonczyk
- Cardiogenetics Research Group, Center of Medical Genetics, University of Antwerp and Antwerp University Hospital, Antwerp, Belgium
| | - Bert Vandendriessche
- Cardiogenetics Research Group, Center of Medical Genetics, University of Antwerp and Antwerp University Hospital, Antwerp, Belgium
| | - Małgorzata Dąbrowska
- Laboratory for Molecular, Cellular and Network Excitability, University of Antwerp, Antwerp, Belgium
| | | | - Dorien Schepers
- Cardiogenetics Research Group, Center of Medical Genetics, University of Antwerp and Antwerp University Hospital, Antwerp, Belgium
| | - Lut Van Laer
- Cardiogenetics Research Group, Center of Medical Genetics, University of Antwerp and Antwerp University Hospital, Antwerp, Belgium
| | - Bart L Loeys
- Cardiogenetics Research Group, Center of Medical Genetics, University of Antwerp and Antwerp University Hospital, Antwerp, Belgium
| | - Maaike Alaerts
- Cardiogenetics Research Group, Center of Medical Genetics, University of Antwerp and Antwerp University Hospital, Antwerp, Belgium.
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22
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Ezekian JE, Rehder C, Kishnani PS, Landstrom AP. Interpretation of Incidental Genetic Findings Localizing to Genes Associated With Cardiac Channelopathies and Cardiomyopathies. CIRCULATION-GENOMIC AND PRECISION MEDICINE 2021; 14:e003200. [PMID: 34384235 DOI: 10.1161/circgen.120.003200] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Recent advances in next-genetic sequencing technology have facilitated an expansion in the use of exome and genome sequencing in the research and clinical settings. While this has aided in the genetic diagnosis of individuals with atypical clinical presentations, there has been a marked increase in the number of incidentally identified variants of uncertain diagnostic significance in genes identified as clinically actionable by the American College of Medical Genetics guidelines. Approximately 20 of these genes are associated with cardiac diseases, which carry a significant risk of sudden cardiac death. While identification of at-risk individuals is paramount, increased discovery of incidental variants of uncertain diagnostic significance has placed a burden on the clinician tasked with determining the diagnostic significance of these findings. Herein, we describe the scope of this emerging problem using cardiovascular genetics to illustrate the challenges associated with variants of uncertain diagnostic significance interpretation. We review the evidence for diagnostic weight of these variants, discuss the role of clinical genetics providers in patient care, and put forward general recommendations about the interpretation of incidentally identified variants found with clinical genetic testing.
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Affiliation(s)
- Jordan E Ezekian
- Division of Cardiology, Department of Pediatrics (J.E.E., A.P.L.), Duke University School of Medicine, Durham, NC
| | - Catherine Rehder
- Department of Pathology (C.R.), Duke University School of Medicine, Durham, NC
| | - Priya S Kishnani
- Division of Medical Genetics, Department of Pediatrics (P.S.K.), Duke University School of Medicine, Durham, NC
| | - Andrew P Landstrom
- Division of Cardiology, Department of Pediatrics (J.E.E., A.P.L.), Duke University School of Medicine, Durham, NC.,Department of Cell Biology (A.P.L.), Duke University School of Medicine, Durham, NC
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23
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Kozek K, Wada Y, Sala L, Denjoy I, Egly C, O'Neill MJ, Aiba T, Shimizu W, Makita N, Ishikawa T, Crotti L, Spazzolini C, Kotta MC, Dagradi F, Castelletti S, Pedrazzini M, Gnecchi M, Leenhardt A, Salem JE, Ohno S, Zuo Y, Glazer AM, Mosley JD, Roden DM, Knollmann BC, Blume JD, Extramiana F, Schwartz PJ, Horie M, Kroncke BM. Estimating the Posttest Probability of Long QT Syndrome Diagnosis for Rare KCNH2 Variants. CIRCULATION-GENOMIC AND PRECISION MEDICINE 2021; 14:e003289. [PMID: 34309407 DOI: 10.1161/circgen.120.003289] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND The proliferation of genetic profiling has revealed many associations between genetic variations and disease. However, large-scale phenotyping efforts in largely healthy populations, coupled with DNA sequencing, suggest variants currently annotated as pathogenic are more common in healthy populations than previously thought. In addition, novel and rare variants are frequently observed in genes associated with disease both in healthy individuals and those under suspicion of disease. This raises the question of whether these variants can be useful predictors of disease. To answer this question, we assessed the degree to which the presence of a variant in the cardiac potassium channel gene KCNH2 was diagnostically predictive for the autosomal dominant long QT syndrome. METHODS We estimated the probability of a long QT diagnosis given the presence of each KCNH2 variant using Bayesian methods that incorporated variant features such as changes in variant function, protein structure, and in silico predictions. We call this estimate the posttest probability of disease. Our method was applied to over 4000 individuals heterozygous for 871 missense or in-frame insertion/deletion variants in KCNH2 and validated against a separate international cohort of 933 individuals heterozygous for 266 missense or in-frame insertion/deletion variants. RESULTS Our method was well-calibrated for the observed fraction of heterozygotes diagnosed with long QT syndrome. Heuristically, we found that the innate diagnostic information one learns about a variant from 3-dimensional variant location, in vitro functional data, and in silico predictors is equivalent to the diagnostic information one learns about that same variant by clinically phenotyping 10 heterozygotes. Most importantly, these data can be obtained in the absence of any clinical observations. CONCLUSIONS We show how variant-specific features can inform a prior probability of disease for rare variants even in the absence of clinically phenotyped heterozygotes.
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Affiliation(s)
- Krystian Kozek
- Vanderbilt Center for Arrhythmia Research and Therapeutics (VanCART), Departments of Medicine & Pharmacology (K.K., Y.W., C.E., M.J.O., A.M.G., J.D.M., D.M.R., B.C.K., B.M.K.), Vanderbilt University Medical Center, Nashville, TN
| | - Yuko Wada
- Vanderbilt Center for Arrhythmia Research and Therapeutics (VanCART), Departments of Medicine & Pharmacology (K.K., Y.W., C.E., M.J.O., A.M.G., J.D.M., D.M.R., B.C.K., B.M.K.), Vanderbilt University Medical Center, Nashville, TN.,Department of Cardiovascular Medicine, Shiga University of Medical Science, Otsu, Japan (Y.W., S.O., M.H.)
| | - Luca Sala
- Laboratory of Cardiovascular Genetics, Istituto Auxologico Italiano IRCCS, Cusano Milanino, Italy (L.S., L.C., C.K., M.P., P.J.S.)
| | - Isabelle Denjoy
- CNMR Maladies Cardiaques Héréditaires Rares, AP-HP, Hôpital Bichat, Paris, France (I.D., A.L., F.E.)
| | - Christian Egly
- Vanderbilt Center for Arrhythmia Research and Therapeutics (VanCART), Departments of Medicine & Pharmacology (K.K., Y.W., C.E., M.J.O., A.M.G., J.D.M., D.M.R., B.C.K., B.M.K.), Vanderbilt University Medical Center, Nashville, TN
| | - Matthew J O'Neill
- Vanderbilt Center for Arrhythmia Research and Therapeutics (VanCART), Departments of Medicine & Pharmacology (K.K., Y.W., C.E., M.J.O., A.M.G., J.D.M., D.M.R., B.C.K., B.M.K.), Vanderbilt University Medical Center, Nashville, TN
| | - Takeshi Aiba
- Department of Cardiovascular Medicine (T.A., N.M., S.O.), National Cerebral and Cardiovascular Center, Suita
| | - Wataru Shimizu
- Department of Cardiovascular Medicine, Graduate School of Medicine, Nippon Medical School, Tokyo, Japan (W.S.)
| | - Naomasa Makita
- Department of Cardiovascular Medicine (T.A., N.M., S.O.), National Cerebral and Cardiovascular Center, Suita.,7Omics Research Center (N.M., T.I.), National Cerebral and Cardiovascular Center, Suita
| | - Taisuke Ishikawa
- 7Omics Research Center (N.M., T.I.), National Cerebral and Cardiovascular Center, Suita
| | - Lia Crotti
- Laboratory of Cardiovascular Genetics, Istituto Auxologico Italiano IRCCS, Cusano Milanino, Italy (L.S., L.C., C.K., M.P., P.J.S.).,Department of Cardiovascular, Neural & Metabolic Sciences, San Luca Hospital (L.C.), Istituto Auxologico Italiano IRCCS.,Center for Cardiac Arrhythmias of Genetic Origin (L.C., C.S., F.D., S.C., P.J.S.), Istituto Auxologico Italiano IRCCS.,Department of Medicine and Surgery, University Milano Bicocca, Milan (L.C.)
| | - Carla Spazzolini
- Center for Cardiac Arrhythmias of Genetic Origin (L.C., C.S., F.D., S.C., P.J.S.), Istituto Auxologico Italiano IRCCS
| | | | - Federica Dagradi
- Center for Cardiac Arrhythmias of Genetic Origin (L.C., C.S., F.D., S.C., P.J.S.), Istituto Auxologico Italiano IRCCS
| | - Silvia Castelletti
- Center for Cardiac Arrhythmias of Genetic Origin (L.C., C.S., F.D., S.C., P.J.S.), Istituto Auxologico Italiano IRCCS
| | - Matteo Pedrazzini
- Laboratory of Cardiovascular Genetics, Istituto Auxologico Italiano IRCCS, Cusano Milanino, Italy (L.S., L.C., C.K., M.P., P.J.S.)
| | - Massimiliano Gnecchi
- Department of Molecular Medicine, Unit of Cardiology, University of Pavia (M.G.).,Intensive Cardiac Care Unit and Lab of Experimental Cardiology for Cell and Molecular Therapy, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy (M.G.)
| | - Antoine Leenhardt
- CNMR Maladies Cardiaques Héréditaires Rares, AP-HP, Hôpital Bichat, Paris, France (I.D., A.L., F.E.).,University de Paris (A.L., F.E.)
| | - Joe-Elie Salem
- Division of Cardiovascular Medicine, Cardio-oncology Program (J.-E.S.), Vanderbilt University Medical Center, Nashville, TN.,Sorbonne Université, INSERM CIC-1901, AP-HP, Department of Pharmacology, Regional Pharmacovigilance Center, Pitié-Salpêtrière Hospital, Paris, France (J.-E.S.)
| | - Seiko Ohno
- Department of Cardiovascular Medicine, Shiga University of Medical Science, Otsu, Japan (Y.W., S.O., M.H.).,Department of Cardiovascular Medicine (T.A., N.M., S.O.), National Cerebral and Cardiovascular Center, Suita
| | - Yi Zuo
- Department of Biostatistics (Y.Z., J.D.M., D.M.R.), Vanderbilt University, Nashville, TN
| | - Andrew M Glazer
- Vanderbilt Center for Arrhythmia Research and Therapeutics (VanCART), Departments of Medicine & Pharmacology (K.K., Y.W., C.E., M.J.O., A.M.G., J.D.M., D.M.R., B.C.K., B.M.K.), Vanderbilt University Medical Center, Nashville, TN
| | - Jonathan D Mosley
- Vanderbilt Center for Arrhythmia Research and Therapeutics (VanCART), Departments of Medicine & Pharmacology (K.K., Y.W., C.E., M.J.O., A.M.G., J.D.M., D.M.R., B.C.K., B.M.K.), Vanderbilt University Medical Center, Nashville, TN.,Department of Biostatistics (Y.Z., J.D.M., D.M.R.), Vanderbilt University, Nashville, TN.,Biomedical Informatics (J.D.M.), Vanderbilt University, Nashville, TN
| | - Dan M Roden
- Vanderbilt Center for Arrhythmia Research and Therapeutics (VanCART), Departments of Medicine & Pharmacology (K.K., Y.W., C.E., M.J.O., A.M.G., J.D.M., D.M.R., B.C.K., B.M.K.), Vanderbilt University Medical Center, Nashville, TN.,Department of Biostatistics (Y.Z., J.D.M., D.M.R.), Vanderbilt University, Nashville, TN
| | - Bjorn C Knollmann
- Vanderbilt Center for Arrhythmia Research and Therapeutics (VanCART), Departments of Medicine & Pharmacology (K.K., Y.W., C.E., M.J.O., A.M.G., J.D.M., D.M.R., B.C.K., B.M.K.), Vanderbilt University Medical Center, Nashville, TN
| | | | - Fabrice Extramiana
- CNMR Maladies Cardiaques Héréditaires Rares, AP-HP, Hôpital Bichat, Paris, France (I.D., A.L., F.E.).,University de Paris (A.L., F.E.)
| | - Peter J Schwartz
- Laboratory of Cardiovascular Genetics, Istituto Auxologico Italiano IRCCS, Cusano Milanino, Italy (L.S., L.C., C.K., M.P., P.J.S.).,Center for Cardiac Arrhythmias of Genetic Origin (L.C., C.S., F.D., S.C., P.J.S.), Istituto Auxologico Italiano IRCCS
| | - Minoru Horie
- Department of Cardiovascular Medicine, Shiga University of Medical Science, Otsu, Japan (Y.W., S.O., M.H.)
| | - Brett M Kroncke
- Vanderbilt Center for Arrhythmia Research and Therapeutics (VanCART), Departments of Medicine & Pharmacology (K.K., Y.W., C.E., M.J.O., A.M.G., J.D.M., D.M.R., B.C.K., B.M.K.), Vanderbilt University Medical Center, Nashville, TN
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24
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Abstract
The physiological heart function is controlled by a well-orchestrated interplay of different ion channels conducting Na+, Ca2+ and K+. Cardiac K+ channels are key players of cardiac repolarization counteracting depolarizating Na+ and Ca2+ currents. In contrast to Na+ and Ca2+, K+ is conducted by many different channels that differ in activation/deactivation kinetics as well as in their contribution to different phases of the action potential. Together with modulatory subunits these K+ channel α-subunits provide a wide range of repolarizing currents with specific characteristics. Moreover, due to expression differences, K+ channels strongly influence the time course of the action potentials in different heart regions. On the other hand, the variety of different K+ channels increase the number of possible disease-causing mutations. Up to now, a plethora of gain- as well as loss-of-function mutations in K+ channel forming or modulating proteins are known that cause severe congenital cardiac diseases like the long-QT-syndrome, the short-QT-syndrome, the Brugada syndrome and/or different types of atrial tachyarrhythmias. In this chapter we provide a comprehensive overview of different K+ channels in cardiac physiology and pathophysiology.
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25
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Stiles MK, Wilde AAM, Abrams DJ, Ackerman MJ, Albert CM, Behr ER, Chugh SS, Cornel MC, Gardner K, Ingles J, James CA, Juang JMJ, Kääb S, Kaufman ES, Krahn AD, Lubitz SA, MacLeod H, Morillo CA, Nademanee K, Probst V, Saarel EV, Sacilotto L, Semsarian C, Sheppard MN, Shimizu W, Skinner JR, Tfelt-Hansen J, Wang DW. 2020 APHRS/HRS expert consensus statement on the investigation of decedents with sudden unexplained death and patients with sudden cardiac arrest, and of their families. J Arrhythm 2021; 37:481-534. [PMID: 34141003 PMCID: PMC8207384 DOI: 10.1002/joa3.12449] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2020] [Accepted: 10/14/2020] [Indexed: 12/26/2022] Open
Abstract
This international multidisciplinary document intends to provide clinicians with evidence-based practical patient-centered recommendations for evaluating patients and decedents with (aborted) sudden cardiac arrest and their families. The document includes a framework for the investigation of the family allowing steps to be taken, should an inherited condition be found, to minimize further events in affected relatives. Integral to the process is counseling of the patients and families, not only because of the emotionally charged subject, but because finding (or not finding) the cause of the arrest may influence management of family members. The formation of multidisciplinary teams is essential to provide a complete service to the patients and their families, and the varied expertise of the writing committee was formulated to reflect this need. The document sections were divided up and drafted by the writing committee members according to their expertise. The recommendations represent the consensus opinion of the entire writing committee, graded by Class of Recommendation and Level of Evidence. The recommendations were opened for public comment and reviewed by the relevant scientific and clinical document committees of the Asia Pacific Heart Rhythm Society (APHRS) and the Heart Rhythm Society (HRS); the document underwent external review and endorsement by the partner and collaborating societies. While the recommendations are for optimal care, it is recognized that not all resources will be available to all clinicians. Nevertheless, this document articulates the evaluation that the clinician should aspire to provide for patients with sudden cardiac arrest, decedents with sudden unexplained death, and their families.
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Affiliation(s)
- Martin K Stiles
- Waikato Clinical School Faculty of Medicine and Health Science The University of Auckland Hamilton New Zealand
| | - Arthur A M Wilde
- Heart Center Department of Clinical and Experimental Cardiology Amsterdam University Medical Center University of Amsterdam Amsterdam the Netherlands
| | | | | | | | - Elijah R Behr
- Cardiovascular Clinical Academic Group, Molecular and Clinical Sciences Institute St George's University of London, and St George's University Hospitals NHS Foundation Trust London UK
| | | | - Martina C Cornel
- Amsterdam University Medical Center Vrije Universiteit Amsterdam Clinical Genetics Amsterdam Public Health Research Institute Amsterdam the Netherlands
| | | | - Jodie Ingles
- Agnes Ginges Centre for Molecular Cardiology at Centenary Institute The University of Sydney Sydney Australia
| | | | - Jyh-Ming Jimmy Juang
- Cardiovascular Center and Division of Cardiology Department of Internal Medicine National Taiwan University Hospital and National Taiwan University College of Medicine Taipei Taiwan
| | - Stefan Kääb
- Department of Medicine I University Hospital LMU Munich Munich Germany
| | | | | | | | - Heather MacLeod
- Data Coordinating Center for the Sudden Death in the Young Case Registry Okemos MI USA
| | | | - Koonlawee Nademanee
- Chulalongkorn University Faculty of Medicine, and Pacific Rim Electrophysiology Research Institute at Bumrungrad Hospital Bangkok Thailand
| | | | - Elizabeth V Saarel
- Cleveland Clinic Lerner College of Cardiology at Case Western Reserve University Cleveland OH USA
- St Luke's Medical Center Boise ID USA
| | - Luciana Sacilotto
- Heart Institute University of São Paulo Medical School São Paulo Brazil
| | - Christopher Semsarian
- Agnes Ginges Centre for Molecular Cardiology at Centenary Institute The University of Sydney Sydney Australia
| | - Mary N Sheppard
- Cardiovascular Clinical Academic Group, Molecular and Clinical Sciences Institute St George's University of London, and St George's University Hospitals NHS Foundation Trust London UK
| | - Wataru Shimizu
- Department of Cardiovascular Medicine Nippon Medical School Tokyo Japan
| | | | - Jacob Tfelt-Hansen
- Department of Forensic Medicine Faculty of Medical Sciences Rigshospitalet Copenhagen Denmark
| | - Dao Wu Wang
- The First Affiliated Hospital of Nanjing Medical University Nanjing China
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26
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Beckmann BM, Scheiper-Welling S, Wilde AAM, Kääb S, Schulze-Bahr E, Kauferstein S. Clinical utility gene card for: Long-QT syndrome. Eur J Hum Genet 2021; 29:1825-1832. [PMID: 34031550 PMCID: PMC8633377 DOI: 10.1038/s41431-021-00904-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Revised: 03/25/2021] [Accepted: 04/23/2021] [Indexed: 11/09/2022] Open
Affiliation(s)
- Britt M Beckmann
- Department of Legal Medicine, University Hospital Frankfurt, Frankfurt am Main, Germany. .,Department of Medicine I, University Hospital, LMU Munich, Munich, Germany.
| | | | - Arthur A M Wilde
- Amsterdam UMC, University of Amsterdam, Heart Center, Amsterdam, The Netherlands.,European Reference Network for Rare and Low Prevalence Complex Diseases of the Heart (ERN GUARDHEART; http://guardheart.ern-net.eu), Amsterdam, The Netherlands.,Department of Clinical and Experimental Cardiology, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands
| | - Stefan Kääb
- Department of Medicine I, University Hospital, LMU Munich, Munich, Germany.,German Center for Cardiovascular Research (DZHK), Partnersite Munich, Munich, Germany
| | - Eric Schulze-Bahr
- European Reference Network for Rare and Low Prevalence Complex Diseases of the Heart (ERN GUARDHEART; http://guardheart.ern-net.eu), Amsterdam, The Netherlands.,Institute for Genetics of Heart Diseases, University Hospital Münster, Münster, Germany
| | - Silke Kauferstein
- Department of Legal Medicine, University Hospital Frankfurt, Frankfurt am Main, Germany
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27
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Chatterjee D, Pieroni M, Fatah M, Charpentier F, Cunningham KS, Spears DA, Chatterjee D, Suna G, Bos JM, Ackerman MJ, Schulze-Bahr E, Dittmann S, Notarstefano PG, Bolognese L, Duru F, Saguner AM, Hamilton RM. An autoantibody profile detects Brugada syndrome and identifies abnormally expressed myocardial proteins. Eur Heart J 2021; 41:2878-2890. [PMID: 32533187 DOI: 10.1093/eurheartj/ehaa383] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/13/2019] [Revised: 03/23/2020] [Accepted: 04/24/2020] [Indexed: 12/17/2022] Open
Abstract
AIMS Brugada syndrome (BrS) is characterized by a unique electrocardiogram (ECG) pattern and life-threatening arrhythmias. However, the Type 1 Brugada ECG pattern is often transient, and a genetic cause is only identified in <25% of patients. We sought to identify an additional biomarker for this rare condition. As myocardial inflammation may be present in BrS, we evaluated whether myocardial autoantibodies can be detected in these patients. METHODS AND RESULTS For antibody (Ab) discovery, normal human ventricular myocardial proteins were solubilized and separated by isoelectric focusing (IEF) and molecular weight on two-dimensional (2D) gels and used to discover Abs by plating with sera from patients with BrS and control subjects. Target proteins were identified by mass spectrometry (MS). Brugada syndrome subjects were defined based on a consensus clinical scoring system. We assessed discovery and validation cohorts by 2D gels, western blots, and ELISA. We performed immunohistochemistry on myocardium from BrS subjects (vs. control). All (3/3) 2D gels exposed to sera from BrS patients demonstrated specific Abs to four proteins, confirmed by MS to be α-cardiac actin, α-skeletal actin, keratin, and connexin-43, vs. 0/8 control subjects. All (18/18) BrS subjects from our validation cohorts demonstrated the same Abs, confirmed by western blots, vs. 0/24 additional controls. ELISA optical densities for all Abs were elevated in all BrS subjects compared to controls. In myocardium obtained from BrS subjects, each protein, as well as SCN5A, demonstrated abnormal protein expression in aggregates. CONCLUSION A biomarker profile of autoantibodies against four cardiac proteins, namely α-cardiac actin, α-skeletal actin, keratin, and connexin-43, can be identified from sera of BrS patients and is highly sensitive and specific, irrespective of genetic cause for BrS. The four involved proteins, along with the SCN5A-encoded Nav1.5 alpha subunit are expressed abnormally in the myocardium of patients with BrS.
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Affiliation(s)
- Diptendu Chatterjee
- Department of Pediatrics, The Labatt Family Heart Centre and Translational Medicine, The Hospital for Sick Children & Research Institute and the University of Toronto, Room 1725D, 555 University Avenue, Toronto, ON M5G 1X8, Canada
| | - Maurizio Pieroni
- Cardiovascular Department, San Donato Hospital, Via Curtatone 54 - 52100 Arezzo, Italy
| | - Meena Fatah
- Department of Pediatrics, The Labatt Family Heart Centre and Translational Medicine, The Hospital for Sick Children & Research Institute and the University of Toronto, Room 1725D, 555 University Avenue, Toronto, ON M5G 1X8, Canada
| | - Flavien Charpentier
- L'Institut du Thorax, INSERM, CNRS, UNIV Nantes, 8 quai Moncousu, 44007 Nantes, France
| | - Kristopher S Cunningham
- Department of Laboratory Medicine and Pathobiology, University of Toronto, 27 King's College Circle, Toronto, Ontario M5S 1A1, Canada
| | - Danna A Spears
- Department of Medicine, University Health Network-Toronto General Hospital, 200 Elizabeth Street 4NU-492, Toronto, Ontario M5G 2C4, Canada
| | - Dipashree Chatterjee
- Department of Psychology, University of Toronto, 27 King's College Circle, Toronto, Ontario M5S 1A1, Canada
| | - Gonca Suna
- Department of Cardiology, University Heart Center Zurich, Rämistrasse 100, 8091 Zürich, Switzerland
| | - J Martjin Bos
- Department of Cardiovascular Medicine, Division of Heart Rhythm Services, Windland Smith Rice Genetic Heart Rhythm Clinic, Mayo Clinic, Rochester, MN, USA.,Department of Pediatric and Adolescent Medicine, Division of Pediatric Cardiology, Mayo Clinic, Rochester, MN, USA.,Department of Molecular Pharmacology and Experimental Therapeutics, Windland Smith Rice Sudden Death Genomics Laboratory, Mayo Clinic, Rochester, MN, USA
| | - Michael J Ackerman
- Department of Cardiovascular Medicine, Division of Heart Rhythm Services, Windland Smith Rice Genetic Heart Rhythm Clinic, Mayo Clinic, Rochester, MN, USA.,Department of Pediatric and Adolescent Medicine, Division of Pediatric Cardiology, Mayo Clinic, Rochester, MN, USA.,Department of Molecular Pharmacology and Experimental Therapeutics, Windland Smith Rice Sudden Death Genomics Laboratory, Mayo Clinic, Rochester, MN, USA
| | - Eric Schulze-Bahr
- Institute for Genetics of Heart Diseases, Department für Kardiologie und Angiologie, Zentrum für Innere Medizin, Universitätsklinikum Münster Albert-Schweitzer-Campus 1, Gebäude D3 48149 Münster, Germany
| | - Sven Dittmann
- Institute for Genetics of Heart Diseases, Department für Kardiologie und Angiologie, Zentrum für Innere Medizin, Universitätsklinikum Münster Albert-Schweitzer-Campus 1, Gebäude D3 48149 Münster, Germany
| | | | - Leonardo Bolognese
- Cardiovascular Department, San Donato Hospital, Via Curtatone 54 - 52100 Arezzo, Italy
| | - Firat Duru
- Department of Cardiology, University Heart Center Zurich, Rämistrasse 100, 8091 Zürich, Switzerland
| | - Ardan M Saguner
- Department of Cardiology, University Heart Center Zurich, Rämistrasse 100, 8091 Zürich, Switzerland
| | - Robert M Hamilton
- Department of Pediatrics, The Labatt Family Heart Centre and Translational Medicine, The Hospital for Sick Children & Research Institute and the University of Toronto, Room 1725D, 555 University Avenue, Toronto, ON M5G 1X8, Canada
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28
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González-Garrido A, Domínguez-Pérez M, Jacobo-Albavera L, López-Ramírez O, Guevara-Chávez JG, Zepeda-García O, Iturralde P, Carnevale A, Villarreal-Molina T. Compound Heterozygous KCNQ1 Mutations Causing Recessive Romano-Ward Syndrome: Functional Characterization by Mutant Co-expression. Front Cardiovasc Med 2021; 8:625449. [PMID: 33693037 PMCID: PMC7937651 DOI: 10.3389/fcvm.2021.625449] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2020] [Accepted: 01/11/2021] [Indexed: 11/13/2022] Open
Abstract
Next Generation Sequencing has identified many KCNQ1 genetic variants associated with type 1 long QT or Romano-Ward syndrome, most frequently inherited in an autosomal dominant fashion, although recessive forms have been reported. Particularly in the case of missense variants, functional studies of mutants are of aid to establish variant pathogenicity and to understand the mechanistic basis of disease. Two compound heterozygous KCNQ1 mutations (p.A300T and p.P535T) were previously found in a child who suffered sudden death. To provide further insight into the clinical significance and basis for pathogenicity of these variants, different combinations of wildtype, A300T and P535T alleles were co-expressed with the accessory β-subunit minK in HEK293 cells, to analyze colocalization with the plasma membrane and some biophysical phenotypes of homo and heterotetrameric channels using the patch-clamp technique. A300T homotetrameric channels showed left-shifted activation V1/2 as previously observed in Xenopus oocytes, decreased maximum conductance density, slow rise-time300ms, and a characteristic use-dependent response. A300T slow rise-time300ms and use-dependent response behaved as dominant biophysical traits for all allele combinations. The P535T variant significantly decreased maximum conductance density and Kv7.1-minK-plasma membrane colocalization. P535T/A300T heterotetrameric channels showed decreased colocalization with plasma membrane, slow rise-time300ms and the A300T characteristic use-dependent response. While A300T left shifted activation voltage dependence behaved as a recessive trait when co-expressed with WT alleles, it was dominant when co-expressed with P535T alleles. Conclusions: The combination of P535T/A300T channel biophysical properties is compatible with recessive Romano Ward syndrome. Further analysis of other biophysical traits may identify other mechanisms involved in the pathophysiology of this disease.
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Affiliation(s)
- Antonia González-Garrido
- Laboratorio de Genómica de Enfermedades Cardiovasculares, Instituto Nacional de Medicina Genómica, Mexico City, Mexico.,Cátedras CONACyT, Consejo Nacional de Ciencia y Tecnología, Mexico City, Mexico
| | - Mayra Domínguez-Pérez
- Laboratorio de Genómica de Enfermedades Cardiovasculares, Instituto Nacional de Medicina Genómica, Mexico City, Mexico
| | - Leonor Jacobo-Albavera
- Laboratorio de Genómica de Enfermedades Cardiovasculares, Instituto Nacional de Medicina Genómica, Mexico City, Mexico
| | - Omar López-Ramírez
- Department of Neurobiology, University of Chicago, Chicago, IL, United States
| | - José Guadalupe Guevara-Chávez
- Laboratorio de Genómica de Enfermedades Cardiovasculares, Instituto Nacional de Medicina Genómica, Mexico City, Mexico
| | - Oscar Zepeda-García
- Laboratorio de Genómica de Enfermedades Cardiovasculares, Instituto Nacional de Medicina Genómica, Mexico City, Mexico
| | - Pedro Iturralde
- Departamento de Electrofisiología, Instituto Nacional de Cardiología "Ignacio Chávez", Mexico, Mexico
| | - Alessandra Carnevale
- Laboratorio de Enfermedades Mendelianas, Instituto Nacional de Medicina Genómica, Mexico, Mexico
| | - Teresa Villarreal-Molina
- Laboratorio de Genómica de Enfermedades Cardiovasculares, Instituto Nacional de Medicina Genómica, Mexico City, Mexico
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29
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Guelly C, Abilova Z, Nuralinov O, Panzitt K, Akhmetova A, Rakhimova S, Kozhamkulov U, Kairov U, Molkenov A, Seisenova A, Trajanoski S, Abildinova Rashbayeva G, Kaussova G, Windpassinger C, Lee JH, Zhumadilov Z, Bekbossynova M, Akilzhanova A. Patients with coronary heart disease, dilated cardiomyopathy and idiopathic ventricular tachycardia share overlapping patterns of pathogenic variation in cardiac risk genes. PeerJ 2021; 9:e10711. [PMID: 33552729 PMCID: PMC7821765 DOI: 10.7717/peerj.10711] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2020] [Accepted: 12/15/2020] [Indexed: 12/22/2022] Open
Abstract
Background Ventricular tachycardia (VT) is a major cause of sudden cardiac death (SCD). Clinical investigations can sometimes fail to identify the underlying cause of VT and the event is classified as idiopathic (iVT). VT contributes significantly to the morbidity and mortality in patients with coronary artery disease (CAD) and dilated cardiomyopathy (DCM). Since mutations in arrhythmia-associated genes frequently determine arrhythmia susceptibility screening for disease-predisposing variants could improve VT diagnostics and prevent SCD in patients. Methods Ninety-two patients diagnosed with coronary heart disease (CHD), DCM, or iVT were included in our study. We evaluated genetic profiles and variants in known cardiac risk genes by targeted next generation sequencing (NGS) using a newly designed custom panel of 96 genes. We hypothesized that shared morphological and phenotypical features among these subgroups may have an overlapping molecular base. To our knowledge, this was the first study of the deep sequencing of 96 targeted cardiac genes in Kazakhstan. The clinical significance of the sequence variants was interpreted according to the guidelines developed by the American College of Medical Genetics and Genomics (ACMG) and the Association for Molecular Pathology (AMP) in 2015. The ClinVar and Varsome databases were used to determine the variant classifications. Results Targeted sequencing and stepwise filtering of the annotated variants identified a total of 307 unique variants in 74 genes, totally 456 variants in the overall study group. We found 168 mutations listed in the Human Genome Mutation Database (HGMD) and another 256 rare/unique variants with elevated pathogenic potential. There was a predominance of high- to intermediate pathogenicity variants in LAMA2, MYBPC3, MYH6, KCNQ1, GAA, and DSG2 in CHD VT patients. Similar frequencies were observed in DCM VT, and iVT patients, pointing to a common molecular disease association. TTN, GAA, LAMA2, and MYBPC3 contained the most variants in the three subgroups which confirm the impact of these genes in the complex pathogenesis of cardiomyopathies and VT. The classification of 307 variants according to ACMG guidelines showed that nine (2.9%) variants could be classified as pathogenic, nine (2.9%) were likely pathogenic, 98 (31.9%) were of uncertain significance, 73 (23.8%) were likely benign, and 118 (38.4%) were benign. CHD VT patients carry rare genetic variants with increased pathogenic potential at a comparable frequency to DCM VT and iVT patients in genes related to sarcomere function, nuclear function, ion flux, and metabolism. Conclusions In this study we showed that in patients with VT secondary to coronary artery disease, DCM, or idiopathic etiology multiple rare mutations and clinically significant sequence variants in classic cardiac risk genes associated with cardiac channelopathies and cardiomyopathies were found in a similar pattern and at a comparable frequency.
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Affiliation(s)
- Christian Guelly
- Center of Medical Research, Medical University of Graz, Graz, Austria
| | - Zhannur Abilova
- Laboratory of Genomic and Personalized Medicine, Center for Life Science, National Laboratory Astana, Nazarbayev University, Nur-Sultan, Kazakhstan
| | | | - Katrin Panzitt
- Center of Medical Research, Medical University of Graz, Graz, Austria
| | - Ainur Akhmetova
- Laboratory of Genomic and Personalized Medicine, Center for Life Science, National Laboratory Astana, Nazarbayev University, Nur-Sultan, Kazakhstan
| | - Saule Rakhimova
- Laboratory of Genomic and Personalized Medicine, Center for Life Science, National Laboratory Astana, Nazarbayev University, Nur-Sultan, Kazakhstan
| | - Ulan Kozhamkulov
- Laboratory of Genomic and Personalized Medicine, Center for Life Science, National Laboratory Astana, Nazarbayev University, Nur-Sultan, Kazakhstan
| | - Ulykbek Kairov
- Laboratory of Bioinformatics and Systems Biology, Center for Life Sciences, National Laboratory Astana, Nazarbayev University, Nur-Sultan, Kazakhstan
| | - Askhat Molkenov
- Laboratory of Bioinformatics and Systems Biology, Center for Life Sciences, National Laboratory Astana, Nazarbayev University, Nur-Sultan, Kazakhstan
| | - Ainur Seisenova
- Laboratory of Bioinformatics and Systems Biology, Center for Life Sciences, National Laboratory Astana, Nazarbayev University, Nur-Sultan, Kazakhstan
| | - Slave Trajanoski
- Center of Medical Research, Medical University of Graz, Graz, Austria
| | | | | | | | - Joseph H Lee
- Sergievsky Center Taub Institute, Columbia University Medical Center, New York, NY, United States of America
| | - Zhaxybay Zhumadilov
- Laboratory of Genomic and Personalized Medicine, Center for Life Science, National Laboratory Astana, Nazarbayev University, Nur-Sultan, Kazakhstan
| | | | - Ainur Akilzhanova
- Laboratory of Genomic and Personalized Medicine, Center for Life Science, National Laboratory Astana, Nazarbayev University, Nur-Sultan, Kazakhstan
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Stiles MK, Wilde AAM, Abrams DJ, Ackerman MJ, Albert CM, Behr ER, Chugh SS, Cornel MC, Gardner K, Ingles J, James CA, Jimmy Juang JM, Kääb S, Kaufman ES, Krahn AD, Lubitz SA, MacLeod H, Morillo CA, Nademanee K, Probst V, Saarel EV, Sacilotto L, Semsarian C, Sheppard MN, Shimizu W, Skinner JR, Tfelt-Hansen J, Wang DW. 2020 APHRS/HRS expert consensus statement on the investigation of decedents with sudden unexplained death and patients with sudden cardiac arrest, and of their families. Heart Rhythm 2021; 18:e1-e50. [PMID: 33091602 PMCID: PMC8194370 DOI: 10.1016/j.hrthm.2020.10.010] [Citation(s) in RCA: 130] [Impact Index Per Article: 43.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Accepted: 10/09/2020] [Indexed: 12/13/2022]
Abstract
This international multidisciplinary document intends to provide clinicians with evidence-based practical patient-centered recommendations for evaluating patients and decedents with (aborted) sudden cardiac arrest and their families. The document includes a framework for the investigation of the family allowing steps to be taken, should an inherited condition be found, to minimize further events in affected relatives. Integral to the process is counseling of the patients and families, not only because of the emotionally charged subject, but because finding (or not finding) the cause of the arrest may influence management of family members. The formation of multidisciplinary teams is essential to provide a complete service to the patients and their families, and the varied expertise of the writing committee was formulated to reflect this need. The document sections were divided up and drafted by the writing committee members according to their expertise. The recommendations represent the consensus opinion of the entire writing committee, graded by Class of Recommendation and Level of Evidence. The recommendations were opened for public comment and reviewed by the relevant scientific and clinical document committees of the Asia Pacific Heart Rhythm Society (APHRS) and the Heart Rhythm Society (HRS); the document underwent external review and endorsement by the partner and collaborating societies. While the recommendations are for optimal care, it is recognized that not all resources will be available to all clinicians. Nevertheless, this document articulates the evaluation that the clinician should aspire to provide for patients with sudden cardiac arrest, decedents with sudden unexplained death, and their families.
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Affiliation(s)
- Martin K Stiles
- Waikato Clinical School, Faculty of Medicine and Health Science, The University of Auckland, Hamilton, New Zealand
| | - Arthur A M Wilde
- Amsterdam University Medical Center, University of Amsterdam, Heart Center, Department of Clinical and Experimental Cardiology, Amsterdam, the Netherlands
| | | | | | | | - Elijah R Behr
- Cardiovascular Clinical Academic Group, Molecular and Clinical Sciences Institute, St George's, University of London, and St George's University Hospitals NHS Foundation Trust, London, United Kingdom
| | - Sumeet S Chugh
- Cedars-Sinai Medical Center, Los Angeles, California, USA
| | - Martina C Cornel
- Amsterdam University Medical Center, Vrije Universiteit Amsterdam, Clinical Genetics, Amsterdam Public Health Research Institute, Amsterdam, the Netherlands
| | | | - Jodie Ingles
- Agnes Ginges Centre for Molecular Cardiology at Centenary Institute, The University of Sydney, Sydney, Australia
| | | | - Jyh-Ming Jimmy Juang
- Cardiovascular Center and Division of Cardiology, Department of Internal Medicine, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei, Taiwan
| | - Stefan Kääb
- Department of Medicine I, University Hospital, LMU Munich, Munich, Germany
| | | | - Andrew D Krahn
- The University of British Columbia, Vancouver, British Columbia, Canada
| | | | - Heather MacLeod
- Data Coordinating Center for the Sudden Death in the Young Case Registry, Okemos, Michigan, USA
| | | | - Koonlawee Nademanee
- Chulalongkorn University, Faculty of Medicine, and Pacific Rim Electrophysiology Research Institute at Bumrungrad Hospital, Bangkok, Thailand
| | | | - Elizabeth V Saarel
- Cleveland Clinic Lerner College of Cardiology at Case Western Reserve University, Cleveland, Ohio, and St Luke's Medical Center, Boise, Idaho, USA
| | - Luciana Sacilotto
- Heart Institute, University of São Paulo Medical School, São Paulo, Brazil
| | - Christopher Semsarian
- Agnes Ginges Centre for Molecular Cardiology at Centenary Institute, The University of Sydney, Sydney, Australia
| | - Mary N Sheppard
- Cardiovascular Clinical Academic Group, Molecular and Clinical Sciences Institute, St George's, University of London, and St George's University Hospitals NHS Foundation Trust, London, United Kingdom
| | - Wataru Shimizu
- Department of Cardiovascular Medicine, Nippon Medical School, Tokyo, Japan
| | - Jonathan R Skinner
- Cardiac Inherited Disease Group, Starship Hospital, Auckland, New Zealand
| | - Jacob Tfelt-Hansen
- Department of Forensic Medicine, Faculty of Medical Sciences, Rigshospitalet, Copenhagen, Denmark
| | - Dao Wu Wang
- The First Affiliated Hospital of Nanjing Medical University, Nanjing, China
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31
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Avidan OR, Tayebi K, Del Toro K, Warrier R. Seizure After Minor Head Trauma: A Red Herring? Clin Pediatr (Phila) 2021; 60:64-66. [PMID: 32723078 DOI: 10.1177/0009922820941643] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Affiliation(s)
| | - Kasra Tayebi
- University of Queensland, Herston, Queensland, Australia
| | - Kamil Del Toro
- University of Queensland, Herston, Queensland, Australia.,Ochsner Children's Hospital, New Orleans, LA, USA
| | - Rajasekharan Warrier
- University of Queensland, Herston, Queensland, Australia.,Ochsner Children's Hospital, New Orleans, LA, USA
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Mahdieh N, Khorgami M, Soveizi M, Seyed Aliakbar S, Dalili M, Rabbani B. Genetic homozygosity in a diverse population: An experience of long QT syndrome. Int J Cardiol 2020; 316:117-124. [PMID: 32470535 DOI: 10.1016/j.ijcard.2020.05.056] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/17/2020] [Revised: 05/02/2020] [Accepted: 05/18/2020] [Indexed: 11/20/2022]
Abstract
BACKGROUND Genomic variations have shown an ethnic-specific pattern within various cohorts. Genetic variants of KCNQ1, KCNH2, SCN5A and KCNE1 causing LQT syndrome have been described in many populations. In this article the spectrum of variants of these genes is presented in Iranian patients. METHODS 102 unrelated individuals diagnosed with LQT were enrolled in this study. Clinical and electrocardiogram (ECG) data of 95 patients were documented, and analyzed by expert pediatric cardiologists. Coding regions and exon-intron boundaries were amplified and sequenced. Segregation analysis was done for novel variants as well as in silico analyses. RESULTS Sixty nine of 95 cases (73%) had Schwartz score of ≥3.5. The causal variants were found in 31 cases (9 novel variants). 21 patients had KCNQ1 (LQTS1) of which15 patients were homozygous for KCNQ1 variants, 9 of these patients (29%) had a Jervell and Lange-Nielsen phenotype. 4 patients had KCNH2 (LQTS2) variants, 7 cases had SCN5A had heterozygous variants, and 2 cases had heterozygous variants in KCNE1 (LQTS5). 19 variants were missense, 3 were nonsense, and 3 were frameshifts. There was one large deletion and 3 intronic variants. CONCLUSION The yield of genetic testing and the genotype profile of LQTS patients in Iran is different from reports elsewhere, with lower overall yield and with 48% having homozygous states.
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Affiliation(s)
- Nejat Mahdieh
- Rajaie Cardiovascular Medical and Research Center, Iran University of Medical Sciences, Tehran, Iran; Growth and development research center, Tehran University of Medical Sciences, Tehran, Iran
| | - Mohammadrafi Khorgami
- Rajaie Cardiovascular Medical and Research Center, Iran University of Medical Sciences, Tehran, Iran
| | - Mahdieh Soveizi
- Rajaie Cardiovascular Medical and Research Center, Iran University of Medical Sciences, Tehran, Iran
| | - Saranaz Seyed Aliakbar
- Rajaie Cardiovascular Medical and Research Center, Iran University of Medical Sciences, Tehran, Iran
| | - Mohammad Dalili
- Rajaie Cardiovascular Medical and Research Center, Iran University of Medical Sciences, Tehran, Iran.
| | - Bahareh Rabbani
- Rajaie Cardiovascular Medical and Research Center, Iran University of Medical Sciences, Tehran, Iran; Growth and development research center, Tehran University of Medical Sciences, Tehran, Iran.
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Campuzano O, Sarquella-Brugada G, Cesar S, Arbelo E, Brugada J, Brugada R. Update on Genetic Basis of Brugada Syndrome: Monogenic, Polygenic or Oligogenic? Int J Mol Sci 2020; 21:ijms21197155. [PMID: 32998306 PMCID: PMC7582739 DOI: 10.3390/ijms21197155] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Revised: 09/23/2020] [Accepted: 09/25/2020] [Indexed: 12/13/2022] Open
Abstract
Brugada syndrome is a rare inherited arrhythmogenic disease leading to ventricular fibrillation and high risk of sudden death. In 1998, this syndrome was linked with a genetic variant with an autosomal dominant pattern of inheritance. To date, rare variants identified in more than 40 genes have been potentially associated with this disease. Variants in regulatory regions, combinations of common variants and other genetic alterations are also proposed as potential origins of Brugada syndrome, suggesting a polygenic or oligogenic inheritance pattern. However, most of these genetic alterations remain of questionable causality; indeed, rare pathogenic variants in the SCN5A gene are the only established cause of Brugada syndrome. Comprehensive analysis of all reported genetic alterations identified the origin of disease in no more than 40% of diagnosed cases. Therefore, identifying the cause of this rare arrhythmogenic disease in the many families without a genetic diagnosis is a major current challenge in Brugada syndrome. Additional challenges are interpretation/classification of variants and translation of genetic data into clinical practice. Further studies focused on unraveling the pathophysiological mechanisms underlying the disease are needed. Here we provide an update on the genetic basis of Brugada syndrome.
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Affiliation(s)
- Oscar Campuzano
- Cardiovascular Genetics Centre, University of Girona-IDIBGI, 17190 Girona, Spain
- Medical Science Department, School of Medicine, University of Girona, 17003 Girona, Spain;
- Centro Investigación Biomédica en Red: Enfermedades Cardiovasculares (CIBERCV), 28029 Madrid, Spain; (E.A.); (J.B.)
- Correspondence: (O.C.); (R.B.)
| | - Georgia Sarquella-Brugada
- Medical Science Department, School of Medicine, University of Girona, 17003 Girona, Spain;
- Arrhythmia Unit, Hospital Sant Joan de Déu, University of Barcelona, 08950 Barcelona, Spain;
| | - Sergi Cesar
- Arrhythmia Unit, Hospital Sant Joan de Déu, University of Barcelona, 08950 Barcelona, Spain;
| | - Elena Arbelo
- Centro Investigación Biomédica en Red: Enfermedades Cardiovasculares (CIBERCV), 28029 Madrid, Spain; (E.A.); (J.B.)
- Arrhythmia Unit, Hospital Sant Joan de Déu, University of Barcelona, 08950 Barcelona, Spain;
| | - Josep Brugada
- Centro Investigación Biomédica en Red: Enfermedades Cardiovasculares (CIBERCV), 28029 Madrid, Spain; (E.A.); (J.B.)
- Arrhythmia Unit, Hospital Sant Joan de Déu, University of Barcelona, 08950 Barcelona, Spain;
- Arrhythmia Section, Cardiovascular Institute, Hospital Clinic, University of Barcelona, 08036 Barcelona, Spain
| | - Ramon Brugada
- Cardiovascular Genetics Centre, University of Girona-IDIBGI, 17190 Girona, Spain
- Medical Science Department, School of Medicine, University of Girona, 17003 Girona, Spain;
- Centro Investigación Biomédica en Red: Enfermedades Cardiovasculares (CIBERCV), 28029 Madrid, Spain; (E.A.); (J.B.)
- Familial Cardiomyopathies Unit, Hospital Josep Trueta de Girona, 17007 Girona, Spain
- Correspondence: (O.C.); (R.B.)
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Long QT Syndrome Type 2: Emerging Strategies for Correcting Class 2 KCNH2 ( hERG) Mutations and Identifying New Patients. Biomolecules 2020. [PMID: 32759882 DOI: 10.3390/biom10081144s] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/25/2023] Open
Abstract
Significant advances in our understanding of the molecular mechanisms that cause congenital long QT syndrome (LQTS) have been made. A wide variety of experimental approaches, including heterologous expression of mutant ion channel proteins and the use of inducible pluripotent stem cell-derived cardiomyocytes (iPSC-CMs) from LQTS patients offer insights into etiology and new therapeutic strategies. This review briefly discusses the major molecular mechanisms underlying LQTS type 2 (LQT2), which is caused by loss-of-function (LOF) mutations in the KCNH2 gene (also known as the human ether-à-go-go-related gene or hERG). Almost half of suspected LQT2-causing mutations are missense mutations, and functional studies suggest that about 90% of these mutations disrupt the intracellular transport, or trafficking, of the KCNH2-encoded Kv11.1 channel protein to the cell surface membrane. In this review, we discuss emerging strategies that improve the trafficking and functional expression of trafficking-deficient LQT2 Kv11.1 channel proteins to the cell surface membrane and how new insights into the structure of the Kv11.1 channel protein will lead to computational approaches that identify which KCNH2 missense variants confer a high-risk for LQT2.
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35
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Ono M, Burgess DE, Schroder EA, Elayi CS, Anderson CL, January CT, Sun B, Immadisetty K, Kekenes-Huskey PM, Delisle BP. Long QT Syndrome Type 2: Emerging Strategies for Correcting Class 2 KCNH2 ( hERG) Mutations and Identifying New Patients. Biomolecules 2020; 10:E1144. [PMID: 32759882 PMCID: PMC7464307 DOI: 10.3390/biom10081144] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Revised: 07/25/2020] [Accepted: 07/27/2020] [Indexed: 12/15/2022] Open
Abstract
Significant advances in our understanding of the molecular mechanisms that cause congenital long QT syndrome (LQTS) have been made. A wide variety of experimental approaches, including heterologous expression of mutant ion channel proteins and the use of inducible pluripotent stem cell-derived cardiomyocytes (iPSC-CMs) from LQTS patients offer insights into etiology and new therapeutic strategies. This review briefly discusses the major molecular mechanisms underlying LQTS type 2 (LQT2), which is caused by loss-of-function (LOF) mutations in the KCNH2 gene (also known as the human ether-à-go-go-related gene or hERG). Almost half of suspected LQT2-causing mutations are missense mutations, and functional studies suggest that about 90% of these mutations disrupt the intracellular transport, or trafficking, of the KCNH2-encoded Kv11.1 channel protein to the cell surface membrane. In this review, we discuss emerging strategies that improve the trafficking and functional expression of trafficking-deficient LQT2 Kv11.1 channel proteins to the cell surface membrane and how new insights into the structure of the Kv11.1 channel protein will lead to computational approaches that identify which KCNH2 missense variants confer a high-risk for LQT2.
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Affiliation(s)
- Makoto Ono
- Department of Physiology, Cardiovascular Research Center, Center for Muscle Biology, University of Kentucky, Lexington, KY 40536, USA; (M.O.); (D.E.B.); (E.A.S.)
| | - Don E. Burgess
- Department of Physiology, Cardiovascular Research Center, Center for Muscle Biology, University of Kentucky, Lexington, KY 40536, USA; (M.O.); (D.E.B.); (E.A.S.)
| | - Elizabeth A. Schroder
- Department of Physiology, Cardiovascular Research Center, Center for Muscle Biology, University of Kentucky, Lexington, KY 40536, USA; (M.O.); (D.E.B.); (E.A.S.)
| | | | - Corey L. Anderson
- Cellular and Molecular Arrhythmia Research Program, University of Wisconsin, Madison, WI 53706, USA; (C.L.A.); (C.T.J.)
| | - Craig T. January
- Cellular and Molecular Arrhythmia Research Program, University of Wisconsin, Madison, WI 53706, USA; (C.L.A.); (C.T.J.)
| | - Bin Sun
- Department of Cellular & Molecular Physiology, Loyola University Chicago, Chicago, IL 60153, USA; (B.S.); (K.I.); (P.M.K.-H.)
| | - Kalyan Immadisetty
- Department of Cellular & Molecular Physiology, Loyola University Chicago, Chicago, IL 60153, USA; (B.S.); (K.I.); (P.M.K.-H.)
| | - Peter M. Kekenes-Huskey
- Department of Cellular & Molecular Physiology, Loyola University Chicago, Chicago, IL 60153, USA; (B.S.); (K.I.); (P.M.K.-H.)
| | - Brian P. Delisle
- Department of Physiology, Cardiovascular Research Center, Center for Muscle Biology, University of Kentucky, Lexington, KY 40536, USA; (M.O.); (D.E.B.); (E.A.S.)
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Huang PS, Hsieh CS, Chang SN, Chen JJ, Chiu FC, Wu CK, Hwang JJ, Chuang EY, Tsai CT. Prevalence of sudden arrhythmic death syndrome-related genetic mutations in an Asian cohort of whole genome sequence. Europace 2020; 22:1287-1297. [PMID: 32594176 DOI: 10.1093/europace/euaa092] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2019] [Accepted: 05/20/2020] [Indexed: 11/13/2022] Open
Abstract
AIMS Recently, the spectrum of background mutation in the genes implicated in sudden arrhythmic death syndrome (SADS), has been elucidated in the Caucasian populations. However, this information is largely unknown in the Asian populations. METHODS AND RESULTS We assessed the background rare variants (minor allele frequency < 0.01) of major SADS genes in whole genome sequence data of 1514 healthy Taiwanese subjects from the Taiwan Biobank. We found up to 45% of healthy subjects have a rare variant in at least one of the major SADS genes. Around 3.44% of healthy subjects had multiple mutations in one or multiple genes. The background mutation rates in long QT syndrome, catecholaminergic polymorphic ventricular tachycardia, and arrhythmogenic right ventricular cardiomyopathy genes were similar, but those in Brugada syndrome (BrS) (SCN5A) and hypertrophic cardiomyopathy (HCM) genes (MYBPC3, MYH7, and TNNT2) were higher, compared to those reported in the Caucasian populations. Furthermore, the rate of incidental pathogenic variant was highest in MYBPC3 gene. Finally, the number of variant was proportional to the exon length of the gene (R2 = 0.486, P = 0.0056) but not related to its functional or evolutionary importance (degree of evolutionary conservation) (R2 = 0.0008, P = 0.9218), suggesting that the mutation was random. The ratio of variant number over exon nucleotide length was highest in MYBPC3, MYH7, and TNNT2 genes. CONCLUSION Unique features of background SADS gene mutation in the Asian populations include higher prevalence of incidental variant in HCM, BrS, and long QT 3 (SCN5A) genes. HCM genes have the highest variant number per exon length.
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Affiliation(s)
- Pang-Shuo Huang
- Department of Internal Medicine, National Taiwan University Hospital Yun-Lin Branch, Yun-Lin, Taiwan
| | - Chia-Shan Hsieh
- College of Life Science, Genome and Systems Biology Degree Program, National Taiwan University, Taipei, Taiwan
| | - Sheng-Nan Chang
- Department of Internal Medicine, National Taiwan University Hospital Yun-Lin Branch, Yun-Lin, Taiwan
| | - Jien-Jiun Chen
- Department of Internal Medicine, National Taiwan University Hospital Yun-Lin Branch, Yun-Lin, Taiwan
| | - Fu-Chun Chiu
- Department of Internal Medicine, National Taiwan University Hospital Yun-Lin Branch, Yun-Lin, Taiwan
| | - Cho-Kai Wu
- Division of Cardiology, Department of Internal Medicine and Cardiovascular center, National Taiwan University College of Medicine and Hospital, No. 7, Chung-Shan South Road, Taipei 100, Taiwan
| | - Juey-Jen Hwang
- Division of Cardiology, Department of Internal Medicine and Cardiovascular center, National Taiwan University College of Medicine and Hospital, No. 7, Chung-Shan South Road, Taipei 100, Taiwan
| | - Eric Y Chuang
- College of Life Science, Genome and Systems Biology Degree Program, National Taiwan University, Taipei, Taiwan.,Graduate Institute of Biomedical Electronics and Bioinformatics, National Taiwan University, Taipei, Taiwan
| | - Chia-Ti Tsai
- Division of Cardiology, Department of Internal Medicine and Cardiovascular center, National Taiwan University College of Medicine and Hospital, No. 7, Chung-Shan South Road, Taipei 100, Taiwan.,Graduate Institute of Clinical Medicine, College of Medicine, National Taiwan University, Taipei, Taiwan
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Ohno S, Ozawa J, Fukuyama M, Makiyama T, Horie M. An NGS-based genotyping in LQTS; minor genes are no longer minor. J Hum Genet 2020; 65:1083-1091. [PMID: 32681117 DOI: 10.1038/s10038-020-0805-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Revised: 06/15/2020] [Accepted: 07/07/2020] [Indexed: 11/09/2022]
Abstract
Mutations in KCNQ1, KCNH2, and SCN5A are the major cause of long QT syndrome (LQTS). More than 90% of the genotyped patients have been reported to carry mutations in any of these three genes. Thanks to increasing popularity of next generation sequencer (NGS), novel CACNA1C mutations have been identified among LQTS patients without extra-cardiac phenotypes. We aimed to clarify the frequency of genotypes in LQTS patients in the era of NGS. The study comprised 160 congenital LQTS patients (71 males) registered from November 2015 to September 2018. Inclusion criteria was QTc > 460 ms and Schwartz score ≥ 3. We performed genetic analysis using target gene method by NGS and confirmed the mutations by Sanger method. The median age for genetic screening was 13 (0-68) years. Sixteen patients suffered cardiac arrest, 47 syncope, and 97 were asymptomatic. We identified genetic mutations in 111 (69.4%) patients including 6 CACNA1C (5.4% of the genotyped patients) with 4 asymptomatic patients. Five (3.1%) patients carried double mutations; three out of them with RYR2 and KCNQ1 or KCNH2. In conclusion, CACNA1C screening would be recommended even if the patient is asymptomatic to elucidate the genetic background of the LQTS patients.
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Affiliation(s)
- Seiko Ohno
- Department of Bioscience and Genetics, National Cerebral and Cardiovascular Center, Suita, Japan. .,Center for Epidemiologic Research in Asia, Shiga University of Medical Science, Otsu, Japan. .,Department of Cardiovascular Medicine, Shiga University of Medical Science, Otsu, Japan.
| | - Junichi Ozawa
- Department of Pediatrics, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan
| | - Megumi Fukuyama
- Department of Cardiovascular Medicine, Shiga University of Medical Science, Otsu, Japan
| | - Takeru Makiyama
- Department of Cardiovascular Medicine, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Minoru Horie
- Center for Epidemiologic Research in Asia, Shiga University of Medical Science, Otsu, Japan.,Department of Cardiovascular Medicine, Shiga University of Medical Science, Otsu, Japan
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Keywan C, Holm IA, Poduri A, Brownstein CA, Alexandrescu S, Chen J, Geffre C, Goldstein RD. A de novo BRPF1 variant in a case of Sudden Unexplained Death in Childhood. Eur J Med Genet 2020; 63:104002. [PMID: 32652122 DOI: 10.1016/j.ejmg.2020.104002] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Revised: 06/02/2020] [Accepted: 07/04/2020] [Indexed: 10/23/2022]
Abstract
Sudden Unexplained Death in Childhood (SUDC), the death of a child that remains unexplained after a complete autopsy and investigation, is a rare and poorly understood entity. This case report describes a 3-year-old boy with history of language delay and ptosis, who died suddenly in his sleep without known cause. A pathogenic de novo frameshift mutation in BRPF1, a gene which has been associated with the syndrome of Intellectual Developmental Disorder with Dysmorphic Facies and Ptosis (IDDDFP), was identified during a post-mortem evaluation. The finding of a pathogenic variant in BRPF1, which has not previously been associated with sudden death, in an SUDC case has implications for this child's family and contributes to the broader field of SUDC research. This case demonstrates the utility of post-mortem genetic testing in SUDC.
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Affiliation(s)
- Christine Keywan
- Robert's Program for Sudden Unexpected Death in Pediatrics, Boston Children's Hospital, USA
| | - Ingrid A Holm
- Robert's Program for Sudden Unexpected Death in Pediatrics, Boston Children's Hospital, USA; Division of Genetics and Genomics and Manton Center for Orphan Diseases Research, Boston Children's Hospital, USA; Department of Pediatrics, Harvard Medical School, USA
| | - Annapurna Poduri
- Robert's Program for Sudden Unexpected Death in Pediatrics, Boston Children's Hospital, USA; Epilepsy Genetics Program, Department of Neurology, Boston Children's Hospital, Harvard Medical School, USA
| | - Catherine A Brownstein
- Robert's Program for Sudden Unexpected Death in Pediatrics, Boston Children's Hospital, USA; Division of Genetics and Genomics and Manton Center for Orphan Diseases Research, Boston Children's Hospital, USA; Department of Pediatrics, Harvard Medical School, USA
| | - Sanda Alexandrescu
- Robert's Program for Sudden Unexpected Death in Pediatrics, Boston Children's Hospital, USA; Department of Pathology at Boston Children's Hospital, Harvard Medical School, USA
| | - Jennifer Chen
- Pima County Office of the Medical Examiner, Tucson, AZ, USA
| | | | - Richard D Goldstein
- Robert's Program for Sudden Unexpected Death in Pediatrics, Boston Children's Hospital, USA; Department of Pediatrics, Harvard Medical School, USA; Division of General Pediatrics, Department of Pediatrics, Boston Children's Hospital, Boston, MA, USA.
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39
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Westphal DS, Burkard T, Moscu-Gregor A, Gebauer R, Hessling G, Wolf CM. Reclassification of genetic variants in children with long QT syndrome. Mol Genet Genomic Med 2020; 8:e1300. [PMID: 32383558 PMCID: PMC7506994 DOI: 10.1002/mgg3.1300] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2019] [Revised: 04/16/2020] [Accepted: 04/17/2020] [Indexed: 01/08/2023] Open
Abstract
Background Genes encoding cardiac ion channels or regulating proteins have been associated with the inherited form of long QT syndrome (LQTS). Complex pathophysiology and missing functional studies, however, often bedevil variant interpretation and classification. We aimed to evaluate the rate of change in variant classification based on current interpretation standards and dependent on clinical findings. Methods Medical charts of children with a molecular genetic diagnosis of LQTS presenting at our centers were retrospectively reviewed. Reinterpretation of originally reported variants in genes associated with LQTS was performed based on current knowledge (March 2019) and according to the “Standards and Guidelines for the Interpretation of Sequence Variants” by the ACMG 2015. Results About 84 distinct (likely) pathogenic variants identified in 127 patients were reinterpreted. In 12 variants (12/84, 14.3%), classification changed from (likely) pathogenic to variant of unknown significance (VUS). One of these variants was a hypomorphic allele escaping the standard variant classification. Individuals with variants that downgraded to VUS after reevaluation showed significantly lower Schwartz scores and QTc intervals compared to individuals with unchanged variant characterization. Conclusion This finding confirms genetic variant interpretation as a dynamic process and underlines the importance of ongoing genetic counseling, especially in LQTS patients with minor clinical criteria.
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Affiliation(s)
- Dominik S Westphal
- Institute of Human Genetics, Technical University of Munich, Munich, Germany.,Institute of Human Genetics, Helmholtz Zentrum Munich, Neuherberg, Germany
| | - Tobias Burkard
- Department of Congenital Heart Disease and Pediatric Cardiology, German Heart Center Munich, Technical University of Munich, Munich, Germany
| | | | - Roman Gebauer
- Department of Pediatric Cardiology, Heart Center Leipzig, University of Leipzig, Leipzig, Germany
| | - Gabriele Hessling
- Department of Congenital Heart Disease and Pediatric Cardiology, German Heart Center Munich, Technical University of Munich, Munich, Germany
| | - Cordula M Wolf
- Department of Congenital Heart Disease and Pediatric Cardiology, German Heart Center Munich, Technical University of Munich, Munich, Germany
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Brewer KR, Kuenze G, Vanoye CG, George AL, Meiler J, Sanders CR. Structures Illuminate Cardiac Ion Channel Functions in Health and in Long QT Syndrome. Front Pharmacol 2020; 11:550. [PMID: 32431610 PMCID: PMC7212895 DOI: 10.3389/fphar.2020.00550] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Accepted: 04/09/2020] [Indexed: 12/13/2022] Open
Abstract
The cardiac action potential is critical to the production of a synchronized heartbeat. This electrical impulse is governed by the intricate activity of cardiac ion channels, among them the cardiac voltage-gated potassium (Kv) channels KCNQ1 and hERG as well as the voltage-gated sodium (Nav) channel encoded by SCN5A. Each channel performs a highly distinct function, despite sharing a common topology and structural components. These three channels are also the primary proteins mutated in congenital long QT syndrome (LQTS), a genetic condition that predisposes to cardiac arrhythmia and sudden cardiac death due to impaired repolarization of the action potential and has a particular proclivity for reentrant ventricular arrhythmias. Recent cryo-electron microscopy structures of human KCNQ1 and hERG, along with the rat homolog of SCN5A and other mammalian sodium channels, provide atomic-level insight into the structure and function of these proteins that advance our understanding of their distinct functions in the cardiac action potential, as well as the molecular basis of LQTS. In this review, the gating, regulation, LQTS mechanisms, and pharmacological properties of KCNQ1, hERG, and SCN5A are discussed in light of these recent structural findings.
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Affiliation(s)
- Kathryn R. Brewer
- Center for Structural Biology, Vanderbilt University School of Medicine Basic Sciences, Nashville, TN, United States
- Department of Biochemistry, Vanderbilt University, Nashville, TN, United States
| | - Georg Kuenze
- Center for Structural Biology, Vanderbilt University School of Medicine Basic Sciences, Nashville, TN, United States
- Department of Chemistry, Vanderbilt University, Nashville, TN, United States
| | - Carlos G. Vanoye
- Department of Pharmacology, Feinberg School of Medicine, Northwestern University, Chicago, IL, United States
| | - Alfred L. George
- Department of Pharmacology, Feinberg School of Medicine, Northwestern University, Chicago, IL, United States
| | - Jens Meiler
- Center for Structural Biology, Vanderbilt University School of Medicine Basic Sciences, Nashville, TN, United States
- Department of Chemistry, Vanderbilt University, Nashville, TN, United States
- Department of Pharmacology, Vanderbilt University School of Medicine Basic Sciences, Nashville, TN, United States
- Institute for Drug Discovery, Leipzig University Medical School, Leipzig, Germany
| | - Charles R. Sanders
- Center for Structural Biology, Vanderbilt University School of Medicine Basic Sciences, Nashville, TN, United States
- Department of Biochemistry, Vanderbilt University, Nashville, TN, United States
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Winbo A, Earle N, Marcondes L, Crawford J, Prosser DO, Love DR, Merriman TR, Cadzow M, Stiles R, Donoghue T, Stiles MK, Hayes I, Skinner JR. Genetic testing in Polynesian long QT syndrome probands reveals a lower diagnostic yield and an increased prevalence of rare variants. Heart Rhythm 2020; 17:1304-1311. [PMID: 32229296 DOI: 10.1016/j.hrthm.2020.03.015] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Accepted: 03/13/2020] [Indexed: 12/19/2022]
Abstract
BACKGROUND New Zealand has a multiethnic population and a national cardiac inherited disease registry (Cardiac Inherited Disease Registry New Zealand [CIDRNZ]). Ancestry is reflected in the spectrum and prevalence of genetic variants in long QT syndrome (LQTS). OBJECTIVE The purpose of this study was to study the genetic testing yield and mutation spectrum of CIDRNZ LQTS probands stratified by self-identified ethnicity. METHODS A 15-year retrospective review of clinical CIDRNZ LQTS probands with a Schwartz score of ≥2 who had undergone genetic testing was performed. RESULTS Of the 264 included LQTS probands, 160 (61%) reported as European, 79 (30%) NZ Māori and Pacific peoples (Polynesian), and 25 (9%) Other ethnicities, with comparable clinical characteristics across ethnic groups (cardiac events in 72%; age at presentation 28±19 years; corrected QT interval 512±55 ms). Despite comparable testing (5.3±1.4 LQTS genes), a class III-V LQTS variant was identified in 35% of Polynesian probands as compared with 63% of European and 72% of Other probands (P<.0001). Among variant-positive CIDRNZ LQTS probands (n=148), Polynesians were more likely to have non-missense variants (57% vs 39% and 25% in probands of European and Other ethnicity, respectively; P=.005) as well as long QT syndrome type 1-3 variants not reported elsewhere (71% vs European 22% and Other 28%; P<.0001). Variants found in multiple probands were more likely to be shared within the same ethnic group; P<.01). CONCLUSION Genetic testing of Polynesian LQTS probands has a lower diagnostic yield, despite comparable testing and clinical disease severity. Rare LQTS variants are more common in Polynesian LQTS probands. These data emphasize the importance of increasing the knowledge of genetic variation in the Polynesian population.
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Affiliation(s)
- Annika Winbo
- Department of Physiology, University of Auckland, Auckland, New Zealand; Department of Paediatric and Congenital Cardiac Services, Starship Children's Hospital, Auckland, New Zealand.
| | - Nikki Earle
- Department of Medicine, University of Auckland, Auckland, New Zealand
| | - Luciana Marcondes
- Department of Paediatric and Congenital Cardiac Services, Starship Children's Hospital, Auckland, New Zealand
| | - Jackie Crawford
- Department of Paediatric and Congenital Cardiac Services, Starship Children's Hospital, Auckland, New Zealand
| | - Debra O Prosser
- Diagnostic Genetics, LabPLUS, Auckland City Hospital, Auckland, New Zealand
| | - Donald R Love
- Diagnostic Genetics, LabPLUS, Auckland City Hospital, Auckland, New Zealand
| | - Tony R Merriman
- Department of Physiology, University of Auckland, Auckland, New Zealand
| | - Murray Cadzow
- Department of Biochemistry, University of Otago, Dunedin, New Zealand
| | - Rachael Stiles
- Department of Cardiology, Waikato Hospital, Waikato, New Zealand
| | - Tom Donoghue
- Department of Cardiology, Wellington Hospital, Wellington, New Zealand
| | - Martin K Stiles
- Department of Cardiology, Waikato Hospital, Waikato, New Zealand
| | - Ian Hayes
- Genetic Health Service NZ, Northern Hub, Auckland City Hospital, Auckland, New Zealand
| | - Jonathan R Skinner
- Department of Paediatric and Congenital Cardiac Services, Starship Children's Hospital, Auckland, New Zealand
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Liebrechts-Akkerman G, Liu F, van Marion R, Dinjens WNM, Kayser M. Explaining sudden infant death with cardiac arrhythmias: Complete exon sequencing of nine cardiac arrhythmia genes in Dutch SIDS cases highlights new and known DNA variants. Forensic Sci Int Genet 2020; 46:102266. [PMID: 32145446 DOI: 10.1016/j.fsigen.2020.102266] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2019] [Revised: 01/23/2020] [Accepted: 02/26/2020] [Indexed: 01/11/2023]
Abstract
Previous studies suggested that Sudden Infant Death Syndrome (SIDS) can partially be genetically explained by cardiac arrhythmias; however, the number of individuals and populations investigated remain limited. We report the first SIDS study on cardiac arrhythmias genes from the Netherlands, a country with the lowest SIDS incidence likely due to parent education on awareness of environmental risk factors. By using targeted massively parallel sequencing (MPS) in 142 Dutch SIDS cases, we performed a complete exon screening of all 173 exons from 9 cardiac arrhythmias genes SCN5A, KCNQ1, KCNH2, KCNE1, KCNE2, CACNA1C, CAV3, ANK2 and KCNJ2 (∼34,000 base pairs), that were selected to harbour previously established SIDS-associated DNA variants. Motivated by the poor DNA quality from the paraffin embedded material used, the application of a conservative sequencing quality control protocol resulted in 102 SIDS cases surviving quality control. Amongst the 102 SIDS cases, we identified a total of 40 DNA variants in 8 cardiac arrhythmia genes found in 60 (58.8 %) cases. Statistical analyses using ancestry-adjusted reference population data and multiple test correction revealed that 13 (32.5 %) of the identified DNA variants in 6 cardiac arrhythmia genes were significantly associated with SIDS, which were observed in 15 (14.7 %) SIDS cases. These 13, and another three, DNA variants were classified as likely pathogenic for cardiac arrhythmias using the American College of Medical Genetics guidelines for interpretation of sequence variants. The 16 likely pathogenic DNA variants were found in 16 (15.7 %) SIDS cases, including i) 3 novel DNA variants not recorded in public databases ii) 7 known DNA variants for which significant SIDS association established here was previously unknown, and iii) 6 known DNA variants for which LQTS association was reported previously. By having replicated previously reported SIDS-associated DNA variants located in cardiac arrhythmia genes and by having highlighting novel SIDS-associated DNA variants in such genes, our findings provide additional empirical evidence for the partial genetic explanation of SIDS by cardiac arrhythmias. On a wider note, our study outcome stresses the need for routine post-mortem genetic screening of assumed SIDS cases, particularly for cardiac arrhythmia genes. When put in practise, it will allow preventing further sudden deaths (not only in infants) in the affected families, thereby allowing forensic molecular autopsy not only to provide answers on the cause of death, but moreover to save lives.
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Affiliation(s)
- Germaine Liebrechts-Akkerman
- Department of Genetic Identification, Erasmus MC University Medical Center Rotterdam, Rotterdam, the Netherlands; Department of Pathology, Erasmus MC University Medical Center Rotterdam, Rotterdam, the Netherlands
| | - Fan Liu
- Department of Genetic Identification, Erasmus MC University Medical Center Rotterdam, Rotterdam, the Netherlands; Key Laboratory of Genomic and Precision Medicine, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing, China; University of Chinese Academy of Sciences, Beijing, China
| | - Ronald van Marion
- Department of Pathology, Erasmus MC University Medical Center Rotterdam, Rotterdam, the Netherlands
| | - Winand N M Dinjens
- Department of Pathology, Erasmus MC University Medical Center Rotterdam, Rotterdam, the Netherlands
| | - Manfred Kayser
- Department of Genetic Identification, Erasmus MC University Medical Center Rotterdam, Rotterdam, the Netherlands.
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Ge Y, Ding D, Zhu G, Kwan P, Wang W, Hong Z, Sander JW. Genetic variants in incident SUDEP cases from a community-based prospective cohort with epilepsy. J Neurol Neurosurg Psychiatry 2020; 91:126-131. [PMID: 31776209 DOI: 10.1136/jnnp-2019-321983] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/04/2019] [Revised: 10/21/2019] [Accepted: 11/05/2019] [Indexed: 11/03/2022]
Abstract
OBJECTIVE Sudden unexpected death in epilepsy (SUDEP) is a leading cause of epilepsy-related mortality in young adults. It has been suggested that SUDEP may kill over 20 000 people with epilepsy in China yearly. The aetiology of SUDEP is unclear. Little is known about candidate genes for SUDEP in people of Chinese origin as most studies have ascertained this in Caucasians. No candidate genes for SUDEP in Chinese people have been identified. METHODS We performed whole exome sequencing (WES) in DNA samples collected from five incident cases of SUDEP identified in a large epilepsy cohort in rural China. We filtered rare variants identified from these cases as well as screened for SUDEP, epilepsy, heart disease or respiratory disease-related genes from previous published reports and compared them with publicly available data, living epilepsy controls and ethnicity-match non-epilepsy controls, to identify potential candidate genes for SUDEP. RESULTS After the filtering process, the five cases carried 168 qualified mutations in 167 genes. Among these genetic anomalies, we identified rare variants in SCN5A (1/5:20% in our cases), KIF6 (1/5:20% in our cases) and TBX18 (1/5:20% in our cases) which were absent in 330 living epilepsy control alleles from the same original cohort and 320 ethnicity-match non-epilepsy control alleles. CONCLUSIONS These three genes were previously related to heart disease, providing support to the hypothesis that underlying heart disorder may be a driver of SUDEP risk.
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Affiliation(s)
- Yan Ge
- Department of Neurology, Huashan Hospital, Fudan University, Shanghai, China
| | - Ding Ding
- Institute of Neurology, WHO Collaborating Center for Research and Training in Neurosciences, Huashan Hospital, Fudan University, Shanghai, China
| | - Guoxing Zhu
- Department of Neurology, Huashan Hospital, Fudan University, Shanghai, China
| | - Patrick Kwan
- Department of Neuroscience, Central Clinical School, Monash University, Melbourne, Victoria, Australia
| | - Wenzhi Wang
- Beijing Neurosurgical Institute, Capital Medical University, Beijing, China
| | - Zhen Hong
- Institute of Neurology, WHO Collaborating Center for Research and Training in Neurosciences, Huashan Hospital, Fudan University, Shanghai, China
| | - Josemir W Sander
- NIHR University College London Hospitals Biomedical Research Centre, UCL Queen Square Institute of Neurology, London, United Kingdom.,Stichting Epilepsie Instellingen Nederland (SEIN), Heemstede, the Netherlands
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Abstract
INTRODUCTION: Prolonged QT interval (PQTI) is a cardiac condition widely documented in the mental health literature and linked to psychotropic medication use. Medications notable for contributing to the condition are antipsychotics, antidepressants, and some mood stabilizers. Although additional medication classes and other contributing risk factors are often present, the prudent mental health provider benefits from having a basic understanding of this condition and how to prevent and manage it with safe prescribing practices. AIMS: This guide seeks to provide mental health prescribers with a basic understanding of the risk factors, pathophysiology, identification, and management of PQTI. METHOD: Relevant literature and practice guidelines were reviewed and summarized with a focus on practical interventions for the psychiatric mental health nurse practitioner (PMHNP). RESULTS: One of the primary contributing factors to PQTI development and complications is polypharmacy. Patients with co-occurring medical, mental health, and/or substance use disorders may receive medications from multiple providers. Anticancer drugs, antiarrhythmic medications, and even a number of common antibiotics can increase the QT interval, making it a challenge for even the most experienced mental health provider to monitor medication interactions and side effects that contribute to PQTI. Having a sound knowledge base of these factors can guide safe PMHNP practice. CONCLUSIONS: Decision-making trees grounded in evidence-based research were developed in order to direct thorough assessment and safe treatment of patients requiring psychotropic medications.
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Affiliation(s)
- Rebecca S Swenson
- Rebecca S. Swenson, FNP-BC, APNP, University of Wisconsin-Madison, WI, USA
| | - Kathleen Murphy-Ende
- Kathleen Murphy-Ende, PhD, PsyD, PMHNP-BC, University of Wisconsin-Madison, WI, USA
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Abela M, Sharma S. Abnormal ECG Findings in Athletes: Clinical Evaluation and Considerations. CURRENT TREATMENT OPTIONS IN CARDIOVASCULAR MEDICINE 2019; 21:95. [PMID: 31865466 DOI: 10.1007/s11936-019-0794-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
PURPOSE OF REVIEW Pre-participation cardiovascular evaluation with electrocardiography is normal practice for most sporting bodies. Awareness about sudden cardiac death in athletes and recognizing how screening can help identify vulnerable athletes have empowered different sporting disciplines to invest in the wellbeing of their athletes. RECENT FINDINGS Discerning physiological electrical alterations due to athletic training from those representing cardiac pathology may be challenging. The mode of investigation of affected athletes is dependent on the electrical anomaly and the disease(s) in question. This review will highlight specific pathological ECG patterns that warrant assessment and surveillance, together with an in-depth review of the recommended algorithm for evaluation.
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Affiliation(s)
- Mark Abela
- Cardiology Clinical Academic Group, St. George's, University of London, St. George's University Hospitals NHS Foundation Trust, London, UK.
- University of Malta, Msida, Malta.
| | - Sanjay Sharma
- Cardiology Clinical Academic Group, St. George's, University of London, St. George's University Hospitals NHS Foundation Trust, London, UK
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Carruth ED, Young W, Beer D, James CA, Calkins H, Jing L, Raghunath S, Hartzel DN, Leader JB, Kirchner HL, Smelser DT, Carey DJ, Kelly MA, Sturm AC, Alsaid A, Fornwalt BK, Haggerty CM. Prevalence and Electronic Health Record-Based Phenotype of Loss-of-Function Genetic Variants in Arrhythmogenic Right Ventricular Cardiomyopathy-Associated Genes. CIRCULATION-GENOMIC AND PRECISION MEDICINE 2019; 12:e002579. [PMID: 31638835 DOI: 10.1161/circgen.119.002579] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
BACKGROUND Arrhythmogenic right ventricular cardiomyopathy (ARVC) is associated with variants in desmosome genes. Secondary findings of pathogenic/likely pathogenic variants, primarily loss-of-function (LOF) variants, are recommended for clinical reporting; however, their prevalence and associated phenotype in a general clinical population are not fully characterized. METHODS From whole-exome sequencing of 61 019 individuals in the DiscovEHR cohort, we screened for putative loss-of-function variants in PKP2, DSC2, DSG2, and DSP. We evaluated measures from prior clinical ECG and echocardiograms, manually over-read to evaluate ARVC diagnostic criteria, and performed a PheWAS (phenome-wide association study). Finally, we estimated expected penetrance using Bayesian inference. RESULTS One hundred forty individuals (0.23%; 59±18 years old at last encounter; 33% male) had an ARVC variant (G+). None had an existing diagnosis of ARVC in the electronic health record, nor significant differences in prior ECG or echocardiogram findings compared with matched controls without variants. Several G+ individuals satisfied major repolarization (n=4) and ventricular function (n=5) criteria, but this prevalence matched controls. PheWAS showed no significant associations of other heart disease diagnoses. Combining our best genetic and disease prevalence estimates yields an estimated penetrance of 6.0%. CONCLUSIONS The prevalence of ARVC loss-of-function variants is ≈1:435 in a general clinical population of predominantly European descent, but with limited electronic health record-based evidence of phenotypic association in our population, consistent with a low penetrance estimate. Prospective deep phenotyping and longitudinal follow-up of a large sequenced cohort is needed to determine the true clinical relevance of an incidentally identified ARVC loss-of-function variant.
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Affiliation(s)
- Eric D Carruth
- Department of Imaging Science and Innovation (E.D.C., L.J., S.R., B.K.F., C.M.H.), Geisinger, Danville, PA.,Biomedical and Translational Informatics Institute (E.D.C., L.J., S.R., D.N.H., J.B.L., H.L.K., B.K.F., C.M.H.), Geisinger, Danville, PA
| | - Wilson Young
- The Heart Institute (W.Y., D.B., A.A., B.K.F., C.M.H.), Geisinger, Danville, PA
| | - Dominik Beer
- The Heart Institute (W.Y., D.B., A.A., B.K.F., C.M.H.), Geisinger, Danville, PA
| | - Cynthia A James
- Department of Medicine, Division of Cardiology, Johns Hopkins Medical Center, Baltimore, MD (C.A.J., H.C.)
| | - Hugh Calkins
- Department of Medicine, Division of Cardiology, Johns Hopkins Medical Center, Baltimore, MD (C.A.J., H.C.)
| | - Linyuan Jing
- Department of Imaging Science and Innovation (E.D.C., L.J., S.R., B.K.F., C.M.H.), Geisinger, Danville, PA.,Biomedical and Translational Informatics Institute (E.D.C., L.J., S.R., D.N.H., J.B.L., H.L.K., B.K.F., C.M.H.), Geisinger, Danville, PA
| | - Sushravya Raghunath
- Department of Imaging Science and Innovation (E.D.C., L.J., S.R., B.K.F., C.M.H.), Geisinger, Danville, PA.,Biomedical and Translational Informatics Institute (E.D.C., L.J., S.R., D.N.H., J.B.L., H.L.K., B.K.F., C.M.H.), Geisinger, Danville, PA
| | - Dustin N Hartzel
- Biomedical and Translational Informatics Institute (E.D.C., L.J., S.R., D.N.H., J.B.L., H.L.K., B.K.F., C.M.H.), Geisinger, Danville, PA
| | - Joseph B Leader
- Biomedical and Translational Informatics Institute (E.D.C., L.J., S.R., D.N.H., J.B.L., H.L.K., B.K.F., C.M.H.), Geisinger, Danville, PA
| | - H Lester Kirchner
- Biomedical and Translational Informatics Institute (E.D.C., L.J., S.R., D.N.H., J.B.L., H.L.K., B.K.F., C.M.H.), Geisinger, Danville, PA
| | - Diane T Smelser
- Department of Molecular and Functional Genomics (D.T.S., D.J.C.), Geisinger, Danville, PA
| | - David J Carey
- Department of Molecular and Functional Genomics (D.T.S., D.J.C.), Geisinger, Danville, PA
| | - Melissa A Kelly
- Genomic Medicine Institute (M.A.K., A.C.S.), Geisinger, Danville, PA
| | - Amy C Sturm
- Genomic Medicine Institute (M.A.K., A.C.S.), Geisinger, Danville, PA
| | - Amro Alsaid
- The Heart Institute (W.Y., D.B., A.A., B.K.F., C.M.H.), Geisinger, Danville, PA
| | - Brandon K Fornwalt
- Department of Imaging Science and Innovation (E.D.C., L.J., S.R., B.K.F., C.M.H.), Geisinger, Danville, PA.,Biomedical and Translational Informatics Institute (E.D.C., L.J., S.R., D.N.H., J.B.L., H.L.K., B.K.F., C.M.H.), Geisinger, Danville, PA.,The Heart Institute (W.Y., D.B., A.A., B.K.F., C.M.H.), Geisinger, Danville, PA.,Department of Radiology (B.K.F.), Geisinger, Danville, PA
| | - Christopher M Haggerty
- Department of Imaging Science and Innovation (E.D.C., L.J., S.R., B.K.F., C.M.H.), Geisinger, Danville, PA.,Biomedical and Translational Informatics Institute (E.D.C., L.J., S.R., D.N.H., J.B.L., H.L.K., B.K.F., C.M.H.), Geisinger, Danville, PA.,The Heart Institute (W.Y., D.B., A.A., B.K.F., C.M.H.), Geisinger, Danville, PA
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Mattivi CL, Ye D, Tester DJ, Clemens DJ, Zhou W, Giudicessi JR, Ackerman MJ. Utilization of the genome aggregation database, in silico tools, and heterologous expression patch-clamp studies to identify and demote previously published type 2 long QT syndrome: Causative variants from pathogenic to likely benign. Heart Rhythm 2019; 17:315-323. [PMID: 31493592 DOI: 10.1016/j.hrthm.2019.08.014] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Indexed: 10/26/2022]
Abstract
BACKGROUND Loss-of-function variants in the KCNH2-encoded Kv11.1 potassium channel cause long QT syndrome (LQTS) type 2 (LQT2). Presently, hundreds of KCNH2 missense variants (MVs) have been published as "disease-causative." However, an estimated 10% of rare published LQTS MVs may be "false positives." OBJECTIVE The purpose of this study was to determine which published KCNH2 MVs are likely false positives and warrant demotion to "likely benign" status. METHODS A list of 337 LQT2-associated MVs from 6 large compendia was compiled. MV frequency within the Genome Aggregation Database (gnomAD) (n = 141,352 individuals) was assessed, and MVs were analyzed with 8 in silico tools. Variants with minor allele frequency (MAF) >7*10E-6, the calculated maximum credible frequency of LQT2, and predicted "benign" by all tools were demoted to "likely benign." Ultra-rare variants (n = 8) absent in gnomAD but predicted "benign" by all tools were considered as potential false positives and were characterized functionally using whole-cell patch clamp. RESULTS Overall, 14 of 337 published KCNH2 MVs (4%) were observed at MAF >7*10E-6, whereas 252 of 337 (75%) were absent in gnomAD. Among the latter, 8 variants (I96V, G187S, A203T, P241L, H254Q, G314S, P935S, P963T) were predicted benign by 8 tools and lacked characterization. Patch clamp showed no functional perturbation for these 8 MVs. CONCLUSION This study offers compelling evidence for the demotion of 22 of 337 KCNH2 variants (6.5%) in the literature. Meticulous "pruning" of compendia using exome/genome databases, in silico tools, and in vitro functional studies must be conducted not only for putatively pathogenic LQTS MVs but for the entire field of genetic heart disease.
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Affiliation(s)
- Connor L Mattivi
- Mayo Clinic Graduate School of Biomedical Sciences, Department of Molecular Pharmacology & Experimental Therapeutics, Windland Smith Rice Sudden Death Genomics Laboratory, Mayo Clinic, Rochester, Minnesota
| | - Dan Ye
- Mayo Clinic Graduate School of Biomedical Sciences, Department of Molecular Pharmacology & Experimental Therapeutics, Windland Smith Rice Sudden Death Genomics Laboratory, Mayo Clinic, Rochester, Minnesota
| | - David J Tester
- Mayo Clinic Graduate School of Biomedical Sciences, Department of Molecular Pharmacology & Experimental Therapeutics, Windland Smith Rice Sudden Death Genomics Laboratory, Mayo Clinic, Rochester, Minnesota; Department of Cardiovascular Medicine, Division of Heart Rhythm Services, Mayo Clinic, Rochester, Minnesota
| | - Daniel J Clemens
- Mayo Clinic Graduate School of Biomedical Sciences, Department of Molecular Pharmacology & Experimental Therapeutics, Windland Smith Rice Sudden Death Genomics Laboratory, Mayo Clinic, Rochester, Minnesota
| | - Wei Zhou
- Mayo Clinic Graduate School of Biomedical Sciences, Department of Molecular Pharmacology & Experimental Therapeutics, Windland Smith Rice Sudden Death Genomics Laboratory, Mayo Clinic, Rochester, Minnesota
| | - John R Giudicessi
- Department of Cardiovascular Medicine, Division of Heart Rhythm Services, Mayo Clinic, Rochester, Minnesota
| | - Michael J Ackerman
- Mayo Clinic Graduate School of Biomedical Sciences, Department of Molecular Pharmacology & Experimental Therapeutics, Windland Smith Rice Sudden Death Genomics Laboratory, Mayo Clinic, Rochester, Minnesota; Department of Pediatric and Adolescent Medicine, Division of Pediatric Cardiology, Mayo Clinic, Rochester, Minnesota.
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Hu RM, Tester DJ, Li R, Sun T, Peterson BZ, Ackerman MJ, Makielski JC, Tan BH. Mexiletine rescues a mixed biophysical phenotype of the cardiac sodium channel arising from the SCN5A mutation, N406K, found in LQT3 patients. Channels (Austin) 2019; 12:176-186. [PMID: 29983085 PMCID: PMC6104686 DOI: 10.1080/19336950.2018.1475794] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Introduction: Individual mutations in the SCN5A-encoding cardiac sodium channel α-subunit usually cause a single cardiac arrhythmia disorder, some cause mixed biophysical or clinical phenotypes. Here we report an infant, female patient harboring a N406K mutation in SCN5A with a marked and mixed biophysical phenotype and assess pathogenic mechanisms. Methods and Results: A patient suffered from recurrent seizures during sleep and torsades de pointes with a QTc of 530 ms. Mutational analysis identified a N406K mutation in SCN5A. The mutation was engineered by site-directed mutagenesis and heterologously expressed in HEK293 cells. After 48 hours incubation with and without mexiletine, macroscopic voltage-gated sodium current (INa) was measured with standard whole-cell patch clamp techniques. SCN5A-N406K elicited both a significantly decreased peak INa and a significantly increased late INa compared to wide-type (WT) channels. Furthermore, mexiletine both restored the decreased peak INa of the mutant channel and inhibited the increased late INa of the mutant channel. Conclusion: SCN5A-N406K channel displays both “gain-of-function” in late INa and “loss-of-function” in peak INa density contributing to a mixed biophysical phenotype. Moreover, our finding may provide the first example that mexiletine exerts a dual rescue of both “gain-of-function” and “loss-of-function” of the mutant sodium channel.
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Affiliation(s)
- Rou-Mu Hu
- a Heart Center & Beijing Key Laboratory of Hypertension, Beijing Chaoyang Hospital , Capital Medical University , Beijing , China.,b Division of Cardiovascular Medicine, Department of Medicine , University of Wisconsin , Madison , Wisconsin , USA
| | - David J Tester
- c Departments of Medicine, Pediatrics, and Molecular Pharmacology and Experimental Therapeutics , Mayo Clinic , Rochester , MN , USA
| | - Ryan Li
- d Departments of Pediatrics, and Cellular & Molecular Physiology , Pennsylvania State University College of Medicine , Hershey , PA , USA
| | - Tianyu Sun
- d Departments of Pediatrics, and Cellular & Molecular Physiology , Pennsylvania State University College of Medicine , Hershey , PA , USA
| | - Blaise Z Peterson
- d Departments of Pediatrics, and Cellular & Molecular Physiology , Pennsylvania State University College of Medicine , Hershey , PA , USA
| | - Michael J Ackerman
- c Departments of Medicine, Pediatrics, and Molecular Pharmacology and Experimental Therapeutics , Mayo Clinic , Rochester , MN , USA
| | - Jonathan C Makielski
- b Division of Cardiovascular Medicine, Department of Medicine , University of Wisconsin , Madison , Wisconsin , USA
| | - Bi-Hua Tan
- b Division of Cardiovascular Medicine, Department of Medicine , University of Wisconsin , Madison , Wisconsin , USA.,d Departments of Pediatrics, and Cellular & Molecular Physiology , Pennsylvania State University College of Medicine , Hershey , PA , USA
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Shanks GW, Tester DJ, Ackerman JP, Simpson MA, Behr ER, White SM, Ackerman MJ. Importance of Variant Interpretation in Whole-Exome Molecular Autopsy: Population-Based Case Series. Circulation 2019; 137:2705-2715. [PMID: 29915097 DOI: 10.1161/circulationaha.117.031053] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/10/2017] [Accepted: 11/09/2017] [Indexed: 01/01/2023]
Abstract
BACKGROUND Potentially lethal cardiac channelopathies/cardiomyopathies may underlie a substantial portion of sudden unexplained death in the young (SUDY). The whole-exome molecular autopsy represents the latest approach to postmortem genetic testing for SUDY. However, proper variant adjudication in the setting of SUDY can be challenging. METHODS From January 2012 through December 2013, 25 consecutive cases of SUDY from 1 to 40 years of age (average age at death 27±5.7 years; 13 white, 12 black) from Cook County, Illinois, were referred after a negative (n=16) or equivocal (n=9) conventional autopsy. A whole-exome molecular autopsy with analysis of 99 sudden death-susceptibility genes was performed. The predicted pathogenicity of ultrarare, nonsynonymous variants was determined using the American College of Medical Genetics guidelines. RESULTS Overall, 27 ultrarare nonsynonymous variants were seen in 16/25 (64%) victims of SUDY. Among black individuals, 9/12 (75%) had an ultrarare nonsynonymous variant compared with 7/13 (54%) white individuals. Of the 27 variants, 10 were considered pathogenic or likely pathogenic in 7/25 (28%) individuals in accordance with the American College of Medical Genetics guidelines. Pathogenic/likely pathogenic variants were identified in 5/16 (31%) of autopsy-negative cases and in 2/6 (33%) victims of SUDY with equivocal findings of cardiomyopathy. Overall, 6 pathogenic/likely pathogenic variants in 4/25 (16%) cases were congruent with the phenotypic findings at autopsy and therefore considered clinically actionable. CONCLUSIONS Whole-exome molecular autopsy with gene-specific surveillance is an effective approach for the detection of potential pathogenic variants in SUDY cases. However, systematic variant adjudication is crucial to ensure accurate and proper care for surviving family members.
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Affiliation(s)
- Garrett W Shanks
- Department of Molecular Pharmacology and Experimental Therapeutics, Windland Smith Rice Sudden Death Genomics Laboratory (G.W.S., D.J.T., J.P.A., M.J.A.)
| | - David J Tester
- Department of Molecular Pharmacology and Experimental Therapeutics, Windland Smith Rice Sudden Death Genomics Laboratory (G.W.S., D.J.T., J.P.A., M.J.A.)
| | - Jaeger P Ackerman
- Department of Molecular Pharmacology and Experimental Therapeutics, Windland Smith Rice Sudden Death Genomics Laboratory (G.W.S., D.J.T., J.P.A., M.J.A.)
| | | | - Elijah R Behr
- Molecular and Clinical Sciences Research Institute, St George's University of London, London, United Kingdom (E.R.B.).,Cardiology Clinical Academic Group, St George's University Hospitals' NHS Foundation Trust, London, United Kingdom (E.R.B.)
| | - Steven M White
- Office of the Medical Examiner, County of Cook, Chicago, IL (S.M.W.).,Department of Pathology, Northwestern University Feinberg School of Medicine, Chicago, IL (S.M.W.)
| | - Michael J Ackerman
- Department of Molecular Pharmacology and Experimental Therapeutics, Windland Smith Rice Sudden Death Genomics Laboratory (G.W.S., D.J.T., J.P.A., M.J.A.) .,Department of Cardiovascular Diseases, Division of Heart Rhythm Service (M.J.A.).,Department of Pediatric and Adolescent Medicine, Division of Pediatric Cardiology (M.J.A.), Mayo Clinic, Rochester, MN
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Phenotype-Based High-Throughput Classification of Long QT Syndrome Subtypes Using Human Induced Pluripotent Stem Cells. Stem Cell Reports 2019; 13:394-404. [PMID: 31378668 PMCID: PMC6700479 DOI: 10.1016/j.stemcr.2019.06.007] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2019] [Revised: 06/29/2019] [Accepted: 06/30/2019] [Indexed: 11/23/2022] Open
Abstract
For long QT syndrome (LQTS), recent progress in genome-sequencing technologies enabled the identification of rare genomic variants with diagnostic, prognostic, and therapeutic implications. However, pathogenic stratification of the identified variants remains challenging, especially in variants of uncertain significance. This study aimed to propose a phenotypic cell-based diagnostic assay for identifying LQTS to recognize pathogenic variants in a high-throughput manner suitable for screening. We investigated the response of LQT2-induced pluripotent stem cell (iPSC)-derived cardiomyocytes (iPSC-CMs) following IKr blockade using a multi-electrode array, finding that the response to IKr blockade was significantly smaller than in Control-iPSC-CMs. Furthermore, we found that LQT1-iPSC-CMs and LQT3-iPSC-CMs could be distinguished from Control-iPSC-CMs by IKs blockade and INa blockade, respectively. This strategy might be helpful in compensating for the shortcomings of genetic testing of LQTS patients.
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