51
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Lahrouchi N, Raju H, Lodder EM, Papatheodorou E, Ware JS, Papadakis M, Tadros R, Cole D, Skinner JR, Crawford J, Love DR, Pua CJ, Soh BY, Bhalshankar JD, Govind R, Tfelt-Hansen J, Winkel BG, van der Werf C, Wijeyeratne YD, Mellor G, Till J, Cohen MC, Tome-Esteban M, Sharma S, Wilde AAM, Cook SA, Bezzina CR, Sheppard MN, Behr ER. Utility of Post-Mortem Genetic Testing in Cases of Sudden Arrhythmic Death Syndrome. J Am Coll Cardiol 2017; 69:2134-2145. [PMID: 28449774 PMCID: PMC5405216 DOI: 10.1016/j.jacc.2017.02.046] [Citation(s) in RCA: 183] [Impact Index Per Article: 26.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/07/2016] [Revised: 02/09/2017] [Accepted: 02/14/2017] [Indexed: 12/19/2022]
Abstract
BACKGROUND Sudden arrhythmic death syndrome (SADS) describes a sudden death with negative autopsy and toxicological analysis. Cardiac genetic disease is a likely etiology. OBJECTIVES This study investigated the clinical utility and combined yield of post-mortem genetic testing (molecular autopsy) in cases of SADS and comprehensive clinical evaluation of surviving relatives. METHODS We evaluated 302 expertly validated SADS cases with suitable DNA (median age: 24 years; 65% males) who underwent next-generation sequencing using an extended panel of 77 primary electrical disorder and cardiomyopathy genes. Pathogenic and likely pathogenic variants were classified using American College of Medical Genetics (ACMG) consensus guidelines. The yield of combined molecular autopsy and clinical evaluation in 82 surviving families was evaluated. A gene-level rare variant association analysis was conducted in SADS cases versus controls. RESULTS A clinically actionable pathogenic or likely pathogenic variant was identified in 40 of 302 cases (13%). The main etiologies established were catecholaminergic polymorphic ventricular tachycardia and long QT syndrome (17 [6%] and 11 [4%], respectively). Gene-based rare variants association analysis showed enrichment of rare predicted deleterious variants in RYR2 (p = 5 × 10-5). Combining molecular autopsy with clinical evaluation in surviving families increased diagnostic yield from 26% to 39%. CONCLUSIONS Molecular autopsy for electrical disorder and cardiomyopathy genes, using ACMG guidelines for variant classification, identified a modest but realistic yield in SADS. Our data highlighted the predominant role of catecholaminergic polymorphic ventricular tachycardia and long QT syndrome, especially the RYR2 gene, as well as the minimal yield from other genes. Furthermore, we showed the enhanced utility of combined clinical and genetic evaluation.
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Affiliation(s)
- Najim Lahrouchi
- Heart Centre, Department of Clinical and Experimental Cardiology, Academic Medical Center, Amsterdam, the Netherlands
| | - Hariharan Raju
- Molecular and Clinical Sciences Research Institute, St. George's, University of London, London, United Kingdom; Cardiology Clinical Academic Group, St. George's University Hospitals NHS Foundation Trust, London, United Kingdom
| | - Elisabeth M Lodder
- Heart Centre, Department of Clinical and Experimental Cardiology, Academic Medical Center, Amsterdam, the Netherlands
| | - Efstathios Papatheodorou
- Molecular and Clinical Sciences Research Institute, St. George's, University of London, London, United Kingdom; Cardiology Clinical Academic Group, St. George's University Hospitals NHS Foundation Trust, London, United Kingdom
| | - James S Ware
- National Heart and Lung Institute, Sydney Street, Imperial College London, London, United Kingdom; Royal Brompton & Harefield Hospitals NHS Foundation Trust, London, United Kingdom
| | - Michael Papadakis
- Molecular and Clinical Sciences Research Institute, St. George's, University of London, London, United Kingdom; Cardiology Clinical Academic Group, St. George's University Hospitals NHS Foundation Trust, London, United Kingdom
| | - Rafik Tadros
- Heart Centre, Department of Clinical and Experimental Cardiology, Academic Medical Center, Amsterdam, the Netherlands; Cardiovascular Genetics Center, Department of Medicine, Montreal Heart Institute and Université de Montréal, Montreal, Canada
| | - Della Cole
- Molecular and Clinical Sciences Research Institute, St. George's, University of London, London, United Kingdom; Cardiology Clinical Academic Group, St. George's University Hospitals NHS Foundation Trust, London, United Kingdom
| | - Jonathan R Skinner
- Cardiac Inherited Disease Group New Zealand, Green Lane Paediatric and Congenital Cardiac Services, Starship Children's Hospital, Auckland New Zealand; The University of Auckland, Department of Paediatrics Child and Youth Health, Auckland, New Zealand
| | - Jackie Crawford
- Cardiac Inherited Disease Group New Zealand, Green Lane Paediatric and Congenital Cardiac Services, Starship Children's Hospital, Auckland New Zealand; The University of Auckland, Department of Paediatrics Child and Youth Health, Auckland, New Zealand
| | - Donald R Love
- Cardiac Inherited Disease Group New Zealand, Green Lane Paediatric and Congenital Cardiac Services, Starship Children's Hospital, Auckland New Zealand; The University of Auckland, Department of Paediatrics Child and Youth Health, Auckland, New Zealand
| | - Chee J Pua
- National Heart Centre Singapore, Singapore
| | - Bee Y Soh
- National Heart Centre Singapore, Singapore
| | | | - Risha Govind
- National Heart and Lung Institute, Sydney Street, Imperial College London, London, United Kingdom; Royal Brompton & Harefield Hospitals NHS Foundation Trust, London, United Kingdom
| | | | - Bo G Winkel
- Department of Cardiology, Rigshospitalet, Copenhagen, Denmark
| | - Christian van der Werf
- Heart Centre, Department of Clinical and Experimental Cardiology, Academic Medical Center, Amsterdam, the Netherlands
| | - Yanushi D Wijeyeratne
- Molecular and Clinical Sciences Research Institute, St. George's, University of London, London, United Kingdom; Cardiology Clinical Academic Group, St. George's University Hospitals NHS Foundation Trust, London, United Kingdom
| | - Greg Mellor
- Molecular and Clinical Sciences Research Institute, St. George's, University of London, London, United Kingdom; Cardiology Clinical Academic Group, St. George's University Hospitals NHS Foundation Trust, London, United Kingdom
| | - Jan Till
- Cardiology Clinical Academic Group, St. George's University Hospitals NHS Foundation Trust, London, United Kingdom; National Heart and Lung Institute, Sydney Street, Imperial College London, London, United Kingdom; Royal Brompton & Harefield Hospitals NHS Foundation Trust, London, United Kingdom
| | - Marta C Cohen
- Sheffield Children's NHS Foundation Trust, Sheffield, United Kingdom
| | - Maria Tome-Esteban
- Molecular and Clinical Sciences Research Institute, St. George's, University of London, London, United Kingdom; Cardiology Clinical Academic Group, St. George's University Hospitals NHS Foundation Trust, London, United Kingdom
| | - Sanjay Sharma
- Molecular and Clinical Sciences Research Institute, St. George's, University of London, London, United Kingdom; Cardiology Clinical Academic Group, St. George's University Hospitals NHS Foundation Trust, London, United Kingdom
| | - Arthur A M Wilde
- Heart Centre, Department of Clinical and Experimental Cardiology, Academic Medical Center, Amsterdam, the Netherlands; Princess Al-Jawhara Al-Brahim Centre of Excellence in Research of Hereditary Disorders, Jeddah, Kingdom of Saudi Arabia
| | - Stuart A Cook
- National Heart and Lung Institute, Sydney Street, Imperial College London, London, United Kingdom; National Heart Centre Singapore, Singapore; Duke-National University of Singapore, Singapore
| | - Connie R Bezzina
- Heart Centre, Department of Clinical and Experimental Cardiology, Academic Medical Center, Amsterdam, the Netherlands
| | - Mary N Sheppard
- Molecular and Clinical Sciences Research Institute, St. George's, University of London, London, United Kingdom; Cardiology Clinical Academic Group, St. George's University Hospitals NHS Foundation Trust, London, United Kingdom
| | - Elijah R Behr
- Molecular and Clinical Sciences Research Institute, St. George's, University of London, London, United Kingdom; Cardiology Clinical Academic Group, St. George's University Hospitals NHS Foundation Trust, London, United Kingdom.
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Bagnall RD, Semsarian C. Role of the molecular autopsy in the investigation of sudden cardiac death. PROGRESS IN PEDIATRIC CARDIOLOGY 2017. [DOI: 10.1016/j.ppedcard.2017.02.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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53
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Visser M, Dooijes D, van der Smagt JJ, van der Heijden JF, Doevendans PA, Loh P, Asselbergs FW, Hassink RJ. Next-generation sequencing of a large gene panel in patients initially diagnosed with idiopathic ventricular fibrillation. Heart Rhythm 2017; 14:1035-1040. [PMID: 28087426 DOI: 10.1016/j.hrthm.2017.01.010] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/28/2016] [Indexed: 11/16/2022]
Abstract
BACKGROUND Idiopathic ventricular fibrillation (IVF) is a rare primary cardiac arrhythmia syndrome that is diagnosed in a resuscitated cardiac arrest victim, with documented ventricular fibrillation, in whom no underlying cause is identified after comprehensive clinical evaluation. In some patients, causative genetic mutations are detected that facilitate patient treatment and follow-up. The feasibility of next-generation sequencing (NGS) has increased with its greater availability and decreasing costs. OBJECTIVE The aim of this study was to assess the diagnostic yield of NGS in patients with IVF. METHODS A total of 33 patients initially diagnosed with IVF were included (mean age 53 ± 15 years; 14(42%) men). In all included patients, NGS of 33 genes and the DPP6 haplotype revealed no pathogenic mutations. Genetic screening comprised NGS of a panel of 179 additional genes. Variants with a minor allele frequency of <0.05% were assessed for pathogenicity by using existing mutation databases and in silico predictive algorithms. RESULTS In 1 of 33 patients, a likely pathogenic mutation was detected. The added yield of genetic testing with NGS of 179 additional genes is 3% in patients with IVF. In 15% of patients, 1 or multiple variants of uncertain clinical significance were detected. CONCLUSION The added yield of genetic screening of extended NGS panels in patients initially diagnosed with IVF is minimal. Routine analysis of large diagnostic NGS panels is therefore not recommended.
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Affiliation(s)
- Marloes Visser
- Department of Cardiology, University Medical Centre, Utrecht, The Netherlands; Department of Internal Medicine and Cardiology, Bergman Clinics, Bilthoven, The Netherlands,.
| | - Dennis Dooijes
- Department of Clinical Genetics, University Medical Centre, Utrecht, The Netherlands
| | | | | | - Pieter A Doevendans
- Department of Cardiology, University Medical Centre, Utrecht, The Netherlands
| | - Peter Loh
- Department of Cardiology, University Medical Centre, Utrecht, The Netherlands
| | | | - Rutger J Hassink
- Department of Cardiology, University Medical Centre, Utrecht, The Netherlands; Department of Internal Medicine and Cardiology, Bergman Clinics, Bilthoven, The Netherlands
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54
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Miyatake S, Mitsuhashi S, Hayashi YK, Purevjav E, Nishikawa A, Koshimizu E, Suzuki M, Yatabe K, Tanaka Y, Ogata K, Kuru S, Shiina M, Tsurusaki Y, Nakashima M, Mizuguchi T, Miyake N, Saitsu H, Ogata K, Kawai M, Towbin J, Nonaka I, Nishino I, Matsumoto N. Biallelic Mutations in MYPN, Encoding Myopalladin, Are Associated with Childhood-Onset, Slowly Progressive Nemaline Myopathy. Am J Hum Genet 2017; 100:169-178. [PMID: 28017374 DOI: 10.1016/j.ajhg.2016.11.017] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2016] [Accepted: 11/22/2016] [Indexed: 01/16/2023] Open
Abstract
Nemaline myopathy (NM) is a common form of congenital nondystrophic skeletal muscle disease characterized by muscular weakness of proximal dominance, hypotonia, and respiratory insufficiency but typically not cardiac dysfunction. Wide variation in severity has been reported. Intranuclear rod myopathy is a subtype of NM in which rod-like bodies are seen in the nucleus, and it often manifests as a severe phenotype. Although ten mutant genes are currently known to be associated with NM, only ACTA1 is associated with intranuclear rod myopathy. In addition, the genetic cause remains unclear in approximately 25%-30% of individuals with NM. We performed whole-exome sequencing on individuals with histologically confirmed but genetically unsolved NM. Our study included individuals with milder, later-onset NM and identified biallelic loss-of-function mutations in myopalladin (MYPN) in four families. Encoded MYPN is a sarcomeric protein exclusively localized in striated muscle in humans. Individuals with identified MYPN mutations in all four of these families have relatively mild, childhood- to adult-onset NM with slowly progressive muscle weakness. Walking difficulties were recognized around their forties. Decreased respiratory function, cardiac involvement, and intranuclear rods in biopsied muscle were observed in two individuals. MYPN was localized at the Z-line in control skeletal muscles but was absent from affected individuals. Homozygous knockin mice with a nonsense mutation in Mypn showed Z-streaming and nemaline-like bodies adjacent to a disorganized Z-line on electron microscopy, recapitulating the disease. Our results suggest that MYPN screening should be considered in individuals with mild NM, especially when cardiac problems or intranuclear rods are present.
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55
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Sanchez O, Campuzano O, Fernández-Falgueras A, Sarquella-Brugada G, Cesar S, Mademont I, Mates J, Pérez-Serra A, Coll M, Pico F, Iglesias A, Tirón C, Allegue C, Carro E, Gallego MÁ, Ferrer-Costa C, Hospital A, Bardalet N, Borondo JC, Vingut A, Arbelo E, Brugada J, Castellà J, Medallo J, Brugada R. Natural and Undetermined Sudden Death: Value of Post-Mortem Genetic Investigation. PLoS One 2016; 11:e0167358. [PMID: 27930701 PMCID: PMC5145162 DOI: 10.1371/journal.pone.0167358] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2016] [Accepted: 11/11/2016] [Indexed: 12/15/2022] Open
Abstract
Background Sudden unexplained death may be the first manifestation of an unknown inherited cardiac disease. Current genetic technologies may enable the unraveling of an etiology and the identification of relatives at risk. The aim of our study was to define the etiology of natural deaths, younger than 50 years of age, and to investigate whether genetic defects associated with cardiac diseases could provide a potential etiology for the unexplained cases. Methods and Findings Our cohort included a total of 789 consecutive cases (77.19% males) <50 years old (average 38.6±12.2 years old) who died suddenly from non-violent causes. A comprehensive autopsy was performed according to current forensic guidelines. During autopsy a cause of death was identified in most cases (81.1%), mainly due to cardiac alterations (56.87%). In unexplained cases, genetic analysis of the main genes associated with sudden cardiac death was performed using Next Generation Sequencing technology. Genetic analysis was performed in suspected inherited diseases (cardiomyopathy) and in unexplained death, with identification of potentially pathogenic variants in nearly 50% and 40% of samples, respectively. Conclusions Cardiac disease is the most important cause of sudden death, especially after the age of 40. Close to 10% of cases may remain unexplained after a complete autopsy investigation. Molecular autopsy may provide an explanation for a significant part of these unexplained cases. Identification of genetic variations enables genetic counseling and undertaking of preventive measures in relatives at risk.
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Affiliation(s)
- Olallo Sanchez
- Cardiovascular Genetics Center, University of Girona-IDIBGI, Girona (Spain)
| | - Oscar Campuzano
- Cardiovascular Genetics Center, University of Girona-IDIBGI, Girona (Spain)
- Department of Medical Sciences, School of Medicine, University of Girona, Girona (Spain)
| | - Anna Fernández-Falgueras
- Cardiovascular Genetics Center, University of Girona-IDIBGI, Girona (Spain)
- Cardiovascular Genetics Unit, Hospital Josep Trueta, Girona (Spain)
| | | | - Sergi Cesar
- Arrhythmia Unit, Hospital Sant Joan de Déu, University of Barcelona, Barcelona (Spain)
| | - Irene Mademont
- Cardiovascular Genetics Center, University of Girona-IDIBGI, Girona (Spain)
| | - Jesus Mates
- Cardiovascular Genetics Center, University of Girona-IDIBGI, Girona (Spain)
| | | | - Monica Coll
- Cardiovascular Genetics Center, University of Girona-IDIBGI, Girona (Spain)
| | - Ferran Pico
- Cardiovascular Genetics Center, University of Girona-IDIBGI, Girona (Spain)
| | - Anna Iglesias
- Cardiovascular Genetics Center, University of Girona-IDIBGI, Girona (Spain)
| | - Coloma Tirón
- Cardiovascular Genetics Unit, Hospital Josep Trueta, Girona (Spain)
| | - Catarina Allegue
- Cardiovascular Genetics Center, University of Girona-IDIBGI, Girona (Spain)
| | - Esther Carro
- Arrhythmia Unit, Hospital Sant Joan de Déu, University of Barcelona, Barcelona (Spain)
| | - María Ángeles Gallego
- Forensic Pathology Service, Institut Medicina Legal Ciències Mèdiques Catalunya, Barcelona (Spain)
| | | | - Anna Hospital
- Forensic Pathology Service, Institut Medicina Legal i Ciències Forenses de Catalunya, Girona (Spain)
| | - Narcís Bardalet
- Forensic Pathology Service, Institut Medicina Legal i Ciències Forenses de Catalunya, Girona (Spain)
| | - Juan Carlos Borondo
- Histopathology Unit, Instituto Nacional de Toxicología y Ciencias Forenses, Barcelona (Spain)
| | - Albert Vingut
- Histopathology Unit, Instituto Nacional de Toxicología y Ciencias Forenses, Barcelona (Spain)
| | - Elena Arbelo
- Arrhythmia Unit, Hospital Clinic de Barcelona, University of Barcelona, Barcelona (Spain)
| | - Josep Brugada
- Arrhythmia Unit, Hospital Sant Joan de Déu, University of Barcelona, Barcelona (Spain)
- Arrhythmia Unit, Hospital Clinic de Barcelona, University of Barcelona, Barcelona (Spain)
| | - Josep Castellà
- Forensic Pathology Service, Institut Medicina Legal Ciències Mèdiques Catalunya, Barcelona (Spain)
| | - Jordi Medallo
- Forensic Pathology Service, Institut Medicina Legal Ciències Mèdiques Catalunya, Barcelona (Spain)
| | - Ramon Brugada
- Cardiovascular Genetics Center, University of Girona-IDIBGI, Girona (Spain)
- Department of Medical Sciences, School of Medicine, University of Girona, Girona (Spain)
- Cardiovascular Genetics Unit, Hospital Josep Trueta, Girona (Spain)
- * E-mail:
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56
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Sudden death and cardiac arrest without phenotype: the utility of genetic testing. Trends Cardiovasc Med 2016; 27:207-213. [PMID: 27692676 DOI: 10.1016/j.tcm.2016.08.010] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/20/2016] [Revised: 08/15/2016] [Accepted: 08/24/2016] [Indexed: 12/19/2022]
Abstract
Approximately 4% of sudden cardiac deaths are unexplained [the sudden arrhythmic death syndrome (SADS)], and up to 6-10% of survivors of cardiac arrest do not have an identifiable cardiac abnormality after comprehensive clinical evaluation [idiopathic ventricular fibrillation (IVF)]. Genetic testing may be able to play a role in diagnostics and can be targeted to an underlying phenotype present in family members following clinical evaluation. Alternatively, post-mortem genetic testing (the "molecular autopsy") may diagnose the underlying cause if a clearly pathogenic rare variant is found. Limitations include a modest yield, and the high probability of finding a variant of unknown significance (VUS) leading to a low signal-to-noise ratio. Next generation sequencing enables cost-efficient high throughput screening of a larger number of genes but at the expense of increased genetic noise. The yield from genetic testing is even lower in IVF in the absence of any suggestion of another phenotype in the index case or his/her family, and should be actively discouraged at this time. Future improvements in diagnostic utility include optimization of the use of variant-calling pipelines and shared databases as well as patient-specific models of disease to more accurately assign pathogenicity of variants. Studying "trios" of parents and the index case may better assess the yield of sporadic and recessive disease.
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Ottaviani G, Buja LM. Anatomopathological changes of the cardiac conduction system in sudden cardiac death, particularly in infants: advances over the last 25 years. Cardiovasc Pathol 2016; 25:489-499. [PMID: 27616614 DOI: 10.1016/j.carpath.2016.08.005] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/23/2016] [Revised: 08/04/2016] [Accepted: 08/23/2016] [Indexed: 02/08/2023] Open
Abstract
Sudden cardiac death (SCD) is defined as the unexpected death without an obvious noncardiac cause that occurs within 1 h of witnessed symptom onset (established SCD) or within 24 h of unwitnessed symptom onset (probable SCD). In the United States, its incidence is 69/100,000 per year. Dysfunctions of the cardiac conduction and autonomic nervous systems are known to contribute to SCD pathogenesis, even if most clinicians and cardiovascular pathologists lack experience with detailed examination of the cardiac conduction system and fail to recognize lesions that are crucial to explain the SCD itself. In this review, we sought to describe the advances over the last 25 years in the study of the anatomopathological changes of the conducting tissue, in SCD, in mature hearts and particularly in sudden infant death syndrome (SIDS) and sudden intrauterine unexpected death syndrome (SIUDS), through the articles published in our journal Cardiovascular Pathology (CVP). We carried out an extensive Medline search to retrieve and review all articles published in CVP in which the sudden unexpected death of one or more subjects believed healthy was reported, especially if associated with lesions of the conducting tissue in settings that revealed no other explained causes of death, particularly in infants and fetuses. The cardiac conduction findings of resorptive degeneration, His bundle dispersion, Mahaim fibers, cartilaginous meta-hyperplasia, persistent fetal dispersion, left-sided His bundle, septation of the bifurcation, atrioventricular node dispersion, sinus node hypoplasia, Zahn node, His bundle hypoplasia, atrioventricular node, and His bundle dualism were similarly detected in SIDS and SIUDS victims.
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Affiliation(s)
- Giulia Ottaviani
- "Lino Rossi" Research Center for the Study and Prevention of Unexpected Perinatal Death and Sudden Infant Death Syndrome (SIDS), Department of Biomedical, Surgical, and Dental Sciences, University of Milan, Milan, Italy; Department of Pathology and Laboratory Medicine, The University of Texas Health Science Center at Houston, Houston, TX, USA.
| | - L Maximilian Buja
- Department of Pathology and Laboratory Medicine, The University of Texas Health Science Center at Houston, Houston, TX, USA
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Hata Y, Yoshida K, Kinoshita K, Nishida N. Epilepsy-related sudden unexpected death: targeted molecular analysis of inherited heart disease genes using next-generation DNA sequencing. Brain Pathol 2016; 27:292-304. [PMID: 27135274 DOI: 10.1111/bpa.12390] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2016] [Revised: 04/11/2016] [Accepted: 04/21/2016] [Indexed: 11/27/2022] Open
Abstract
Inherited heart disease causing electric instability in the heart has been suggested to be a risk factor for sudden unexpected death in epilepsy (SUDEP). The purpose of this study was to reveal the correlation between epilepsy-related sudden unexpected death (SUD) and inherited heart disease. Twelve epilepsy-related SUD cases (seven males and five females, aged 11-78 years) were examined. Nine cases fulfilled the criteria of SUDEP, and three cases died by drowning. In addition to examining three major epilepsy-related genes, we used next-generation sequencing (NGS) to examine 73 inherited heart disease-related genes. We detected both known pathogenic variants and rare variants with minor allele frequencies of <0.5%. The pathogenicity of these variants was evaluated and graded by eight in silico predictive algorithms. Six known and six potential rare variants were detected. Among these, three known variants of LDB3, DSC2 and KCNE1 and three potential rare variants of MYH6, DSP and DSG2 were predicted by in silico analysis as possibly highly pathogenic in three of the nine SUDEP cases. Two of three cases with desmosome-related variants showed mild but possible significant right ventricular dysplasia-like pathology. A case with LDB3 and MYH6 variants showed hypertrabeculation of the left ventricle and severe fibrosis of the cardiac conduction system. In the three drowning death cases, one case with mild prolonged QT interval had two variants in ANK2. This study shows that inherited heart disease may be a significant risk factor for SUD in some epilepsy cases, even if pathological findings of the heart had not progressed to an advanced stage of the disease. A combination of detailed pathological examination of the heart and gene analysis using NGS may be useful for evaluating arrhythmogenic potential of epilepsy-related SUD.
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Affiliation(s)
- Yukiko Hata
- Department of Legal Medicine, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Toyama, Japan
| | - Koji Yoshida
- Department of Neurology, Toyama University Hospital, Toyama, Japan
| | - Koshi Kinoshita
- Department of Legal Medicine, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Toyama, Japan
| | - Naoki Nishida
- Department of Legal Medicine, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Toyama, Japan
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Lahrouchi N, Behr ER, Bezzina CR. Next-Generation Sequencing in Post-mortem Genetic Testing of Young Sudden Cardiac Death Cases. Front Cardiovasc Med 2016; 3:13. [PMID: 27303672 PMCID: PMC4885007 DOI: 10.3389/fcvm.2016.00013] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2016] [Accepted: 05/02/2016] [Indexed: 12/19/2022] Open
Abstract
Sudden cardiac death (SCD) in the young (<40 years) occurs in the setting of a variety of rare inherited cardiac disorders and is a disastrous event for family members. Establishing the cause of SCD is important as it permits the pre-symptomatic identification of relatives at risk of SCD. Sudden arrhythmic death syndrome (SADS) is defined as SCD in the setting of negative autopsy findings and toxicological analysis. In such cases, reaching a diagnosis is even more challenging and post-mortem genetic testing can crucially contribute to the identification of the underlying cause of death. In this review, we will discuss the current achievements of “the molecular autopsy” in young SADS cases and provide an overview of key challenges in assessing pathogenicity (i.e., causality) of genetic variants identified through next-generation sequencing.
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Affiliation(s)
- Najim Lahrouchi
- Department of Clinical and Experimental Cardiology, Heart Center, AMC , Amsterdam , Netherlands
| | - Elijah R Behr
- Cardiology Clinical Academic Group, St George's University of London , London , UK
| | - Connie R Bezzina
- Department of Clinical and Experimental Cardiology, Heart Center, AMC , Amsterdam , Netherlands
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60
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Strande NT, Berg JS. Defining the Clinical Value of a Genomic Diagnosis in the Era of Next-Generation Sequencing. Annu Rev Genomics Hum Genet 2016; 17:303-32. [PMID: 27362341 DOI: 10.1146/annurev-genom-083115-022348] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
As with all fields of medicine, the first step toward medical management of genetic disorders is obtaining an accurate diagnosis, which often requires testing at the molecular level. Unfortunately, given the large number of genetic conditions without a specific intervention, only rarely does a genetic diagnosis alter patient management-which raises the question, what is the added value of obtaining a molecular diagnosis? Given the fast-paced advancement of genomic technologies, this is an important question to address in the context of genome-scale testing. Here, we address the value of establishing a diagnosis using genome-scale testing and highlight the benefits and drawbacks of such testing. We also review and compare recent major studies implementing genome-scale sequencing methods to identify a molecular diagnosis in cohorts manifesting a broad range of Mendelian monogenic disorders. Finally, we discuss potential future applications of genomic sequencing, such as screening for rare conditions.
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Affiliation(s)
- Natasha T Strande
- Department of Genetics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599; ,
| | - Jonathan S Berg
- Department of Genetics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599; ,
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