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Gómez González C, Del Campo Cano I, Isabel Fernández-Avila A, Paz Suárez-Mier M, José Sagastizábal M, Álvarez García-Rovés R, Méndez Fernández I, Vilches S, Centeno Jiménez M, Siles Sánchez-Manjavacas A, Usano Carrasco A, Gonzalez-Vioque E, Pablo Ochoa J, Medrano C, González López E, García-Pavía P, Bermejo J, Angeles Espinosa Castro M. Sudden cardiac death triggered by minimal alcohol consumption in the context of novel PPA2 mutations in 2 unrelated families. Gene 2024; 916:148437. [PMID: 38582264 DOI: 10.1016/j.gene.2024.148437] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2024] [Revised: 03/26/2024] [Accepted: 04/02/2024] [Indexed: 04/08/2024]
Abstract
Biallelic variants in PPA2 gene cause a rare but lethal mitochondrial disorder. We describe the first four cases reported in Spain of PPA2 disease in two unrelated families. We have conducted a revision of the clinical history, necropsies, and postmortem genetic testing from probands, and clinical evaluation, genetic testing and blood transcript analysis in family members. All the cases harbored biallelic PPA2 variants in compound heterozygous status. Two brothers from family 1 suffered sudden death after a small first intake of alcohol in 2013 and 2022. The sister remains alive but affected with cardiomyopathy, extensive scar on cardiac imaging, and high sensitivity to alcohol intake. The three siblings carried PPA2 c.290A > G (p.Glu97Gly) novel missense variant and PPA2 c.513C > T (p.Cys171 = ) altering splicing site variant, both probably leading to mRNA degradation based on in-silico and transcript analyses. A teenager from family 2 suffered sudden death after a small intake of alcohol in 2018 and carried PPA2 c.683C > T (p.Pro228Leu) missense and PPA2 c.980_983del (p.Gln327fs) novel frameshift variant, both probably leading to abnormal protein structure. All cases were asymptomatic until adolescence. Furthermore, the sister in family 1 has survived as an asymptomatic adult. PPA2 disease can manifest as cardiac arrest in the young, especially after alcohol exposure. Our results show that PPA2 deficiency can be related to different pathogenicity mechanisms such as abnormal protein structure but also mRNA decay caused by synonymous or missense variants. Strict avoidance of alcohol consumption and early defibrillator implantation might prevent lethal arrhythmias in patients at risk.
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Affiliation(s)
- Cristina Gómez González
- Department of Cardiology, Hospital General Universitario Gregorio Marañón, Madrid, Spain; Facultad de Medicina, Universidad Complutense de Madrid, Spain; Instituto de Investigación Sanitaria Gregorio Marañón, Madrid, Spain; CIBERCV, Spain
| | - Iván Del Campo Cano
- Department of Pediatrics, Hospital Universitario Puerta de Hierro Majadahonda, Madrid, Spain; IDIPHISA, Madrid, Spain
| | - Ana Isabel Fernández-Avila
- Facultad de Medicina, Universidad Complutense de Madrid, Spain; Instituto de Investigación Sanitaria Gregorio Marañón, Madrid, Spain; CIBERCV, Spain.
| | - Maria Paz Suárez-Mier
- Servicio de Histopatología. Instituto Nacional de Toxicología y Ciencias Forenses. Madrid. Spain
| | | | - Reyes Álvarez García-Rovés
- Facultad de Medicina, Universidad Complutense de Madrid, Spain; Instituto de Investigación Sanitaria Gregorio Marañón, Madrid, Spain; Pediatric Cardiology Department, Hospital General Universitario Gregorio Marañón, Madrid, Spain
| | - Irene Méndez Fernández
- Department of Cardiology, Hospital General Universitario Gregorio Marañón, Madrid, Spain; Facultad de Medicina, Universidad Complutense de Madrid, Spain; Instituto de Investigación Sanitaria Gregorio Marañón, Madrid, Spain; CIBERCV, Spain
| | - Silvia Vilches
- Department of Cardiology, Hospital General Universitario Gregorio Marañón, Madrid, Spain; Facultad de Medicina, Universidad Complutense de Madrid, Spain; Instituto de Investigación Sanitaria Gregorio Marañón, Madrid, Spain; CIBERCV, Spain
| | - Miriam Centeno Jiménez
- Facultad de Medicina, Universidad Complutense de Madrid, Spain; Instituto de Investigación Sanitaria Gregorio Marañón, Madrid, Spain; Pediatric Cardiology Department, Hospital General Universitario Gregorio Marañón, Madrid, Spain
| | - Ana Siles Sánchez-Manjavacas
- Department of Pediatrics, Hospital Universitario Puerta de Hierro Majadahonda, Madrid, Spain; IDIPHISA, Madrid, Spain
| | - Ana Usano Carrasco
- Department of Pediatrics, Hospital Universitario Puerta de Hierro Majadahonda, Madrid, Spain; IDIPHISA, Madrid, Spain
| | | | - Juan Pablo Ochoa
- Health in Code. A Coruña. Spain; Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid, Spain
| | - Constancio Medrano
- Facultad de Medicina, Universidad Complutense de Madrid, Spain; Instituto de Investigación Sanitaria Gregorio Marañón, Madrid, Spain; Pediatric Cardiology Department, Hospital General Universitario Gregorio Marañón, Madrid, Spain
| | - Esther González López
- CIBERCV, Spain; IDIPHISA, Madrid, Spain; Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid, Spain
| | - Pablo García-Pavía
- CIBERCV, Spain; IDIPHISA, Madrid, Spain; Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid, Spain; Department of Cardiology, Hospital Universitario Puerta de Hierro, Majadahonda, Madrid, Spain
| | - Javier Bermejo
- Department of Cardiology, Hospital General Universitario Gregorio Marañón, Madrid, Spain; Facultad de Medicina, Universidad Complutense de Madrid, Spain; Instituto de Investigación Sanitaria Gregorio Marañón, Madrid, Spain; CIBERCV, Spain
| | - María Angeles Espinosa Castro
- Department of Cardiology, Hospital General Universitario Gregorio Marañón, Madrid, Spain; Facultad de Medicina, Universidad Complutense de Madrid, Spain; Instituto de Investigación Sanitaria Gregorio Marañón, Madrid, Spain; CIBERCV, Spain
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Graham S, Peterson DC, James C. Alcohol-Induced Sudden Cardiac Death in a Teenager With PPA2 Gene Mutations. Am J Forensic Med Pathol 2023; 44:332-335. [PMID: 37249496 DOI: 10.1097/paf.0000000000000841] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
ABSTRACT The PPA2 gene encodes a mitochondrial pyrophosphatase protein. Mutations in the gene are inherited in an autosomal recessive fashion and, when mutated, function to induce mitochondrial ATP production failure resulting in increased stress on the heart and sudden cardiac death, especially when combined with alcohol. Herein, we describe a case of a 19-year-old female patient with a history of "alcohol intolerance" who was found unexpectedly deceased after consuming a minimal amount of alcohol. Histological examination of her heart revealed widespread fibrosis of the left ventricle and the interventricular septum. Other findings include hypertrophied myocytes, including some with pleomorphic nuclei. Genetic studies were performed on postmortem blood, revealing heterozygous PPA2 gene mutations, the pathogenic variant c.683C>T (p.Pro228Leu), and the other variant c.814C>T (p.His272Tyr), a novel variant of undetermined significance. We propose that the variant of undetermined significance is likely a pathogenic mutation due to the decedent's phenotype.
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Affiliation(s)
- Sydney Graham
- From the Arkansas College of Osteopathic Medicine, Fort Smith, AR
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Genthe W, Donnelly C, Ezon D, Fettig V, Ganesh J, Marin-Valecia I, Gelb BD. PPA2 Deficiency in 2 Sisters: A Rare Cause of Sudden Cardiac Death. JACC Case Rep 2023; 24:102024. [PMID: 37869221 PMCID: PMC10589443 DOI: 10.1016/j.jaccas.2023.102024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2023] [Revised: 08/22/2023] [Accepted: 08/23/2023] [Indexed: 10/24/2023]
Abstract
Inorganic pyrophosphatase 2 (PPA2) deficiency is a genetic cause of sudden cardiac death, often triggered by viral infection or alcohol consumption. Literature on management is limited because most cases are diagnosed post mortem. We report lethal and nonlethal cardiac presentations of PPA2 deficiency in 2 adolescent sisters that resulted from a novel pathogenic PPA2 variant. (Level of Difficulty: Advanced.).
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Affiliation(s)
- Will Genthe
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Colleen Donnelly
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - David Ezon
- Department of Pediatric Cardiology, Icahn School of Medicine at Mount Sinai, Children’s Heart Center, Mount Sinai Hospital, New York, New York, USA
| | - Veronica Fettig
- Department of Pediatric Cardiology, Icahn School of Medicine at Mount Sinai, Children’s Heart Center, Mount Sinai Hospital, New York, New York, USA
- The Zena and Michael A. Wiener Cardiovascular Institute, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Jaya Ganesh
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Isaac Marin-Valecia
- Department of Pediatric Neurology, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Bruce D. Gelb
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, New York, USA
- Department of Pediatric Cardiology, Icahn School of Medicine at Mount Sinai, Children’s Heart Center, Mount Sinai Hospital, New York, New York, USA
- Mindich Child Health and Development Institute, Icahn School of Medicine at Mount Sinai, New York, New York, USA
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Lipov A, Jurgens SJ, Mazzarotto F, Allouba M, Pirruccello JP, Aguib Y, Gennarelli M, Yacoub MH, Ellinor PT, Bezzina CR, Walsh R. Exploring the complex spectrum of dominance and recessiveness in genetic cardiomyopathies. Nat Cardiovasc Res 2023; 2:1078-1094. [PMID: 38666070 PMCID: PMC11041721 DOI: 10.1038/s44161-023-00346-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/07/2023] [Accepted: 09/07/2023] [Indexed: 04/28/2024]
Abstract
Discrete categorization of Mendelian disease genes into dominant and recessive models often oversimplifies their underlying genetic architecture. Cardiomyopathies (CMs) are genetic diseases with complex etiologies for which an increasing number of recessive associations have recently been proposed. Here, we comprehensively analyze all published evidence pertaining to biallelic variation associated with CM phenotypes to identify high-confidence recessive genes and explore the spectrum of monoallelic and biallelic variant effects in established recessive and dominant disease genes. We classify 18 genes with robust recessive association with CMs, largely characterized by dilated phenotypes, early disease onset and severe outcomes. Several of these genes have monoallelic association with disease outcomes and cardiac traits in the UK Biobank, including LMOD2 and ALPK3 with dilated and hypertrophic CM, respectively. Our data provide insights into the complex spectrum of dominance and recessiveness in genetic heart disease and demonstrate how such approaches enable the discovery of unexplored genetic associations.
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Affiliation(s)
- Alex Lipov
- Department of Experimental Cardiology, Heart Centre, Amsterdam UMC, Amsterdam, the Netherlands
- Amsterdam Cardiovascular Sciences, Heart Failure & Arrhythmias, Amsterdam, the Netherlands
| | - Sean J. Jurgens
- Department of Experimental Cardiology, Heart Centre, Amsterdam UMC, Amsterdam, the Netherlands
- Amsterdam Cardiovascular Sciences, Heart Failure & Arrhythmias, Amsterdam, the Netherlands
- Cardiovascular Disease Initiative, Broad Institute of MIT and Harvard, Cambridge, MA USA
- Cardiovascular Research Center, Massachusetts General Hospital, Harvard Medical School, Boston, MA USA
| | - Francesco Mazzarotto
- Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy
- National Heart and Lung Institute, Imperial College London, London, UK
| | - Mona Allouba
- National Heart and Lung Institute, Imperial College London, London, UK
- Aswan Heart Centre, Magdi Yacoub Heart Foundation, Aswan, Egypt
| | - James P. Pirruccello
- Cardiovascular Disease Initiative, Broad Institute of MIT and Harvard, Cambridge, MA USA
- Division of Cardiology, University of California, San Francisco, San Francisco, CA USA
| | - Yasmine Aguib
- National Heart and Lung Institute, Imperial College London, London, UK
- Aswan Heart Centre, Magdi Yacoub Heart Foundation, Aswan, Egypt
| | - Massimo Gennarelli
- Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy
- Genetics Unit, Istituto di Ricovero e Cura a Carattere Scientifico, Istituto Centro San Giovanni di Dio Fatebenefratelli, Brescia, Italy
| | - Magdi H. Yacoub
- National Heart and Lung Institute, Imperial College London, London, UK
- Aswan Heart Centre, Magdi Yacoub Heart Foundation, Aswan, Egypt
- Harefield Heart Science Centre, Uxbridge, UK
| | - Patrick T. Ellinor
- Cardiovascular Disease Initiative, Broad Institute of MIT and Harvard, Cambridge, MA USA
- Cardiovascular Research Center, Massachusetts General Hospital, Harvard Medical School, Boston, MA USA
- Demoulas Center for Cardiac Arrhythmias, Massachusetts General Hospital, Boston, MA USA
| | - Connie R. Bezzina
- Department of Experimental Cardiology, Heart Centre, Amsterdam UMC, Amsterdam, the Netherlands
- Amsterdam Cardiovascular Sciences, Heart Failure & Arrhythmias, Amsterdam, the Netherlands
- European Reference Network for Rare and Low Prevalence Complex Diseases of the Heart, Amsterdam, the Netherlands
| | - Roddy Walsh
- Department of Experimental Cardiology, Heart Centre, Amsterdam UMC, Amsterdam, the Netherlands
- Amsterdam Cardiovascular Sciences, Heart Failure & Arrhythmias, Amsterdam, the Netherlands
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Manzanilla-Romero HH, Schermer E, Mayr A, Rudnik-Schöneborn S. Only one beer can be mortal: a case report of two sisters with cardiac arrest due to a homozygous mutation in PPA2 gene. Eur J Pediatr 2023; 182:3785-3788. [PMID: 37269378 PMCID: PMC10460352 DOI: 10.1007/s00431-023-05034-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Revised: 03/31/2023] [Accepted: 05/19/2023] [Indexed: 06/05/2023]
Abstract
We report the long way to the correct diagnosis in two teenage sisters who developed a cardiac arrest after consuming minimal amounts of alcohol. The older girl dramatically survived two cardiac arrests at the age of 14 and 15 years. She underwent an extensive examination that revealed isolated cardiac abnormalities including fibrosis, dilated cardiomyopathy and inflammation. The younger girl also had a cardiac arrest at the age of 15 and died suddenly after consuming 1-2 beers, 3 years after her sister´s first incident. Autopsy of the heart revealed acute myocarditis without structural alterations. Multigene panel analysis (not including PPA2) showed SCN5A and CACNA1D variants in both sisters and their healthy mother. Six years later duo exome allowed the diagnosis of an autosomal recessive PPA2-related mitochondriopathy. We discuss the molecular results and clinical picture of our patients compared to other PPA2-related cases. We highlight the diagnostic contribution of multigene panels and exome analysis. The genetic diagnosis is important for medical care and for everyday life, specifically because alcohol intake can result in cardiac arrest and should be strictly avoided. Conclusion: Duo exome sequencing clarified the diagnosis of PPA2-related mitochondriopathy in two sisters with isolated cardiac features and sudden cardiac arrest triggered by minimal amounts of alcohol. What is Known: • Multigene-Panel or exome analysis is a valuable tool to identify genetic causes of hereditary cardiac arrhythmias. • Variants of unknown significance can lead to misinterpretation. PPA2-related mitochondriopathy is a very rare autosomal recessive condition that is normally fatal in infancy. What is New: • Duo exome analysis in two teeenage sisters with cardiac arrest revealed a homozygous mild PPA2 mutation as the underlying pathology restricted to the heart muscle.
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Affiliation(s)
| | - Elisabeth Schermer
- Pediatrics III (Cardiopulmonary Unit), Medical University of Innsbruck, Innsbruck, Austria
| | - Agnes Mayr
- Clinic of Radiology, Medical University of Innsbruck, Innsbruck, Austria
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van Deventer BS, Makhoba MA, du Toit-Prinsloo L, van Niekerk C. The added value of molecular-based diagnostics in the African forensic medical setting. Cardiovasc J Afr 2022; 33:282-286. [PMID: 36326683 PMCID: PMC9887432 DOI: 10.5830/cvja-2022-050] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2021] [Accepted: 09/02/2022] [Indexed: 06/16/2023] Open
Abstract
Sudden unexpected infant death (SUDI) is reported to be an extraordinarily high burden in sub-Saharan Africa, with the incidence rate in South Africa among the highest in the world. It is common for the cause of many such infant deaths to remain unexplained even after a full medico-legal death investigation, and then to be categorised as a sudden unexplained infant death (SUID). Fortunately, advances in molecular-based diagnostics allow researchers to identify numerous underlying inherited cardiac arrhythmogenic disorders in many SUDI cases, with a predominance of variants identified in the SCN5A gene. Such cardiac arrhythmogenic-related sudden deaths generally present with no structural alterations of the heart that are macroscopically identifiable at autopsy, therefore highlighting the importance of post mortem genetic testing. We report on a significant genetic finding that was made on a SUDI case in which the cause was ascribed to an acute bacterial pneumonia but it was still subjected to post mortem genetic testing of the SCN5A gene. The literature shows that many SUDI cases diagnosed with inherited cardiac arrhythmogenic disorders have demonstrated a viral prodrome within days of their death. It is therefore not uncommon for these cardiac disorders in infants to be mistaken for flu, viral upper respiratory tract infection or pneumonia, and without the incorporation of post mortem genetic testing, any other contributory causes of these deaths are often disregarded. This study highlights the need for research reporting on the genetics of inherited cardiac disorders in Africa.
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Affiliation(s)
| | - Musa Aubrey Makhoba
- Department of Forensic Medicine, University of Pretoria, Pretoria, South Africa
| | - Lorraine du Toit-Prinsloo
- Department of Forensic Medicine, University of Pretoria, Pretoria, South Africa; Department of Forensic Medicine, Sydney, Australia
| | - Chantal van Niekerk
- Department of Chemical Pathology, University of Pretoria, and Department of Chemical Pathology, National Health Laboratory Services, Pretoria, South Africa
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Halvorsen M, Gould L, Wang X, Grant G, Moya R, Rabin R, Ackerman MJ, Tester DJ, Lin PT, Pappas JG, Maurano MT, Goldstein DB, Tsien RW, Devinsky O. De novo mutations in childhood cases of sudden unexplained death that disrupt intracellular Ca 2+ regulation. Proc Natl Acad Sci U S A 2021; 118:e2115140118. [PMID: 34930847 PMCID: PMC8719874 DOI: 10.1073/pnas.2115140118] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/20/2021] [Indexed: 01/04/2023] Open
Abstract
Approximately 400 United States children 1 y of age and older die suddenly from unexplained causes annually. We studied whole-exome sequence data from 124 “trios” (decedent child and living parents) to identify genetic risk factors. Nonsynonymous mutations, mostly de novo (present in child but absent in both biological parents), were highly enriched in genes associated with cardiac and seizure disorders relative to controls, and contributed to 9% of deaths. We found significant overtransmission of loss-of-function or pathogenic missense variants in cardiac and seizure disorder genes. Most pathogenic variants were de novo in origin, highlighting the importance of trio studies. Many of these pathogenic de novo mutations altered a protein network regulating calcium-related excitability at submembrane junctions in cardiomyocytes and neurons. Sudden unexplained death in childhood (SUDC) is an understudied problem. Whole-exome sequence data from 124 “trios” (decedent child, living parents) was used to test for excessive de novo mutations (DNMs) in genes involved in cardiac arrhythmias, epilepsy, and other disorders. Among decedents, nonsynonymous DNMs were enriched in genes associated with cardiac and seizure disorders relative to controls (odds ratio = 9.76, P = 2.15 × 10−4). We also found evidence for overtransmission of loss-of-function (LoF) or previously reported pathogenic variants in these same genes from heterozygous carrier parents (11 of 14 transmitted, P = 0.03). We identified a total of 11 SUDC proband genotypes (7 de novo, 1 transmitted parental mosaic, 2 transmitted parental heterozygous, and 1 compound heterozygous) as pathogenic and likely contributory to death, a genetic finding in 8.9% of our cohort. Two genes had recurrent missense DNMs, RYR2 and CACNA1C. Both RYR2 mutations are pathogenic (P = 1.7 × 10−7) and were previously studied in mouse models. Both CACNA1C mutations lie within a 104-nt exon (P = 1.0 × 10−7) and result in slowed L-type calcium channel inactivation and lower current density. In total, six pathogenic DNMs can alter calcium-related regulation of cardiomyocyte and neuronal excitability at a submembrane junction, suggesting a pathway conferring susceptibility to sudden death. There was a trend for excess LoF mutations in LoF intolerant genes, where ≥1 nonhealthy sample in denovo-db has a similar variant (odds ratio = 6.73, P = 0.02); additional uncharacterized genetic causes of sudden death in children might be discovered with larger cohorts.
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Zhu W, Jiang H, Xie S, Xiao H, Liu Q, Chen N, Wan P, Lu S. Downregulation of PPA2 expression correlates with poor prognosis of kidney renal clear cell carcinoma. PeerJ 2021; 9:e12086. [PMID: 34567842 PMCID: PMC8428262 DOI: 10.7717/peerj.12086] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Accepted: 08/07/2021] [Indexed: 11/23/2022] Open
Abstract
Background Kidney renal clear cell carcinoma (KIRC) is the most common subtype of kidney cancer. Inorganic pyrophosphatase (PPA2) is an enzyme that catalyzes the hydrolysis of pyrophosphate to inorganic phosphate; few studies have reported its significance in cancers. Therefore, we aimed to explore the prognostic value of PPA2 in KIRC. Methods PPA2 expression was detected via immunohistochemistry in a tissue chip containing specimens from 150 patients with KIRC. We evaluated the correlation between PPA2 expression, clinicopathological characteristics, and survival. Data from online databases and another cohort (paraffin-embedded specimens from 10 patients with KIRC) were used for external validation. Results PPA2 expression was significantly lower in KIRC tissues than in normal renal tissues (p < 0.0001). Low expression of PPA2 was significantly associated with a high histologic grade and poor prognosis. The differential expression of PPA2 was validated at the gene and protein levels. Multivariate Cox regression analysis showed that PPA2 expression was an independent prognostic factor in patients with KIRC. Gene set enrichment analysis suggested that decreased expression of PPA2 might be related to the epithelial-mesenchymal transition in KIRC. Conclusions Our study demonstrated that PPA2 is an important energy metabolism-associated biomarker correlated with a favorable prognosis in KIRC.
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Affiliation(s)
- Wenbiao Zhu
- Department of Pathology, Meizhou People's Hospital, Meizhou, Guangdong, China
| | - Huiming Jiang
- Department of Urology, Meizhou People's Hospital, Meizhou, Guangdong, China
| | - Shoucheng Xie
- Department of Pathology, Meizhou People's Hospital, Meizhou, Guangdong, China
| | - Huanqin Xiao
- Department of Pathology, Meizhou People's Hospital, Meizhou, Guangdong, China
| | - Qinghua Liu
- Department of Pathology, Meizhou People's Hospital, Meizhou, Guangdong, China
| | - Nanhui Chen
- Department of Urology, Meizhou People's Hospital, Meizhou, Guangdong, China
| | - Pei Wan
- Department of Urology, Meizhou People's Hospital, Meizhou, Guangdong, China
| | - Shanming Lu
- Department of Pathology, Meizhou People's Hospital, Meizhou, Guangdong, China
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Guimier A, Achleitner MT, de Bellaing AM, Edwards M, de Pontual L, Mittal K, Dunn KE, Grove ME, Tysoe CJ, Dimartino C, Cameron J, Kanthi A, Shukla A, van den Broek F, Chatterjee D, Alston CL, Knowles CV, Brett L, Till JA, Homfray T, French P, Spentzou G, Elserafy NA, Lichkus KS, Sankaran BP, Kennedy HL, George PM, Kidd A, Wortmann SB, Fisk DG, Koopmann TT, Rafiq MA, Merker JD, Parikh S, Ahimaz P, Weintraub RG, Ma AS, Turner C, Ellaway CJ, Phillips LK, Thorburn DR, Chung WK, Kana SL, Faye-Petersen OM, Thompson ML, Janin A, McLeod K, McGowan R, McFarland R, Girisha KM, Morris-Rosendahl DJ, Hurst ACE, Turner CLS, Hamilton RM, Taylor RW, Bajolle F, Gordon CT, Amiel J, Mayr JA, Doudney K. PPA2-associated sudden cardiac death: extending the clinical and allelic spectrum in 20 new families. Genet Med 2021. [PMID: 34400813 DOI: 10.1038/s41436-021-01296-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2021] [Revised: 07/19/2021] [Accepted: 07/22/2021] [Indexed: 11/30/2022] Open
Abstract
Purpose Biallelic hypomorphic variants in PPA2, encoding the mitochondrial inorganic pyrophosphatase 2 protein, have been recently identified in individuals presenting with sudden cardiac death, occasionally triggered by alcohol intake or a viral infection. Here we report 20 new families harboring PPA2 variants. Methods Synthesis of clinical and molecular data concerning 34 individuals harboring five previously reported PPA2 variants and 12 novel variants, 11 of which were functionally characterized. Results Among the 34 individuals, only 6 remain alive. Twenty-three died before the age of 2 years while five died between 14 and 16 years. Within these 28 cases, 15 died of sudden cardiac arrest and 13 of acute heart failure. One case was diagnosed prenatally with cardiomyopathy. Four teenagers drank alcohol before sudden cardiac arrest. Progressive neurological signs were observed in 2/6 surviving individuals. For 11 variants, recombinant PPA2 enzyme activities were significantly decreased and sensitive to temperature, compared to wild-type PPA2 enzyme activity. Conclusion We expand the clinical and mutational spectrum associated with PPA2 dysfunction. Heart failure and sudden cardiac arrest occur at various ages with inter- and intrafamilial phenotypic variability, and presentation can include progressive neurological disease. Alcohol intake can trigger cardiac arrest and should be strictly avoided.
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Yin Y, Wu Y, Zhang X, Zhu Y, Sun Y, Yu J, Gong Y, Sun P, Lin H, Han X. PPA1 Regulates Systemic Insulin Sensitivity by Maintaining Adipocyte Mitochondria Function as a Novel PPARγ Target Gene. Diabetes 2021; 70:1278-1291. [PMID: 33722839 DOI: 10.2337/db20-0622] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Accepted: 02/28/2021] [Indexed: 11/13/2022]
Abstract
Downregulation of mitochondrial function in adipose tissue is considered as one important driver for the development of obesity-associated metabolic disorders. Inorganic pyrophosphatase 1 (PPA1) is an enzyme that catalyzes the hydrolysis of inorganic pyrophosphate to inorganic phosphate and is required for anabolism to take place in cells. Although alteration of PPA1 has been related to some diseases, the importance of PPA1 in metabolic syndromes has never been discussed. In this study, we found that global PPA1 knockout mice (PPA1+/-) showed impaired glucose tolerance and severe insulin resistance under high-fat-diet feeding. In addition, impaired adipose tissue development and ectopic lipid accumulation were observed. Conversely, overexpression of PPA1 in adipose tissue by adeno-associated virus injection can partly reverse the metabolic disorders in PPA1+/- mice, suggesting that impaired adipose tissue function is responsible for the metabolic disorders observed in PPA1+/- mice. Mechanistic studies revealed that PPA1 acted as a PPARγ target gene to maintain mitochondrial function in adipocytes. Furthermore, specific knockdown of PPA1 in fat body of Drosophila led to impaired mitochondria morphology, decreased lipid storage, and made Drosophila more sensitive to starvation. In conclusion, for the first time, our findings demonstrate the importance of PPA1 in maintaining adipose tissue function and whole-body metabolic homeostasis.
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Affiliation(s)
- Ye Yin
- Key Laboratory of Human Functional Genomics of Jiangsu Province, Department of Biochemistry and Molecular Biology, Nanjing Medical University, Nanjing, Jiangsu, China
| | - Yangyang Wu
- Key Laboratory of Human Functional Genomics of Jiangsu Province, Department of Biochemistry and Molecular Biology, Nanjing Medical University, Nanjing, Jiangsu, China
| | - Xu Zhang
- Key Laboratory of Human Functional Genomics of Jiangsu Province, Department of Biochemistry and Molecular Biology, Nanjing Medical University, Nanjing, Jiangsu, China
| | - Yeting Zhu
- Key Laboratory of Human Functional Genomics of Jiangsu Province, Department of Biochemistry and Molecular Biology, Nanjing Medical University, Nanjing, Jiangsu, China
| | - Yue Sun
- Key Laboratory of Human Functional Genomics of Jiangsu Province, Department of Biochemistry and Molecular Biology, Nanjing Medical University, Nanjing, Jiangsu, China
| | - Jiani Yu
- Key Laboratory of Human Functional Genomics of Jiangsu Province, Department of Biochemistry and Molecular Biology, Nanjing Medical University, Nanjing, Jiangsu, China
| | - Yufei Gong
- Key Laboratory of Human Functional Genomics of Jiangsu Province, Department of Biochemistry and Molecular Biology, Nanjing Medical University, Nanjing, Jiangsu, China
| | - Peng Sun
- Key Laboratory of Human Functional Genomics of Jiangsu Province, Department of Biochemistry and Molecular Biology, Nanjing Medical University, Nanjing, Jiangsu, China
| | - Haiyan Lin
- Key Laboratory of Human Functional Genomics of Jiangsu Province, Department of Biochemistry and Molecular Biology, Nanjing Medical University, Nanjing, Jiangsu, China
| | - Xiao Han
- Key Laboratory of Human Functional Genomics of Jiangsu Province, Department of Biochemistry and Molecular Biology, Nanjing Medical University, Nanjing, Jiangsu, China
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11
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Zhao A, Shen J, Ding Y, Sheng M, Zuo M, Lv H, Wang J, Shen Y, Wang H, Sun L. Long-read sequencing identified a novel nonsense and a de novo missense of PPA2 in trans in a Chinese patient with autosomal recessive infantile sudden cardiac failure. Clin Chim Acta 2021; 519:163-171. [PMID: 33826954 DOI: 10.1016/j.cca.2021.03.029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2021] [Revised: 03/30/2021] [Accepted: 03/31/2021] [Indexed: 10/21/2022]
Abstract
BACKGROUND AND AIMS Biallelic missense variants in PPA2 gene cause infantile sudden cardiac failure (SCFI; OMIM #617222) characterized by sudden cardiac failure, sudden cardiac death in infants. Here, we present an unusual survivor with one inherited plus one de novo variant in PPA2. Since next-generation sequencing (NGS) fails to resolve variant phasing, which require long-read sequencing to clarify the diagnosis. MATERIALS AND METHODS Whole exome and Sanger sequencing were initially performed to identify the causative variants. PCR-based short tandem repeats (STRs) analysis and long-read single molecule real-time (SMRT) sequencing were further implemented for paternity testing and variant phasing. Pathogenicity evaluation of the biallelic variants in PPA2 was conducted according to the American College of Medical Genetics and Genomics (ACMG) and the Association for Molecular Pathology (AMP) guidelines based on VarSome. RESULTS Whole exome and Sanger sequencing revealed two variants in PPA2, with one novel nonsense variant (c.524C > G; p.Ser175*) inherited from the mother and one de novo missense variant (c.379C > T; p.Arg127Cys). PCR-based STRs analysis verified the paternity. And long-read SMRT sequencing phased the two variants in trans and identified the paternal origin of the de novo variant. The genetic diagnosis clarified the genetic etiology of the proband and assisted in patient management and counseling. CONCLUSION We identified a rare combination of one inherited plus one de novo variant of PPA2 in a patient with autosomal recessive SCFI, which expanded the mutation spectrum of PPA2 and demonstrated the power of target long-read sequencing to make up the diagnostic gap of prevailing NGS.
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Affiliation(s)
- Arman Zhao
- Department of Clinical Laboratory, Children's Hospital of Soochow University, 92 Zhongnan Street, Suzhou Industrial Park, Suzhou 215025, Jiangsu, China.
| | - Jie Shen
- Department of Cardiology, Children's Hospital of Soochow University, 92 Zhongnan Street, Suzhou Industrial Park, Suzhou 215025, Jiangsu, China.
| | - Yueyue Ding
- Department of Cardiology, Children's Hospital of Soochow University, 92 Zhongnan Street, Suzhou Industrial Park, Suzhou 215025, Jiangsu, China.
| | - Mao Sheng
- Department of Radiology, Children's Hospital of Soochow University, 92 Zhongnan Street, Suzhou Industrial Park, Suzhou 215025, Jiangsu, China.
| | - Mengying Zuo
- Department of Cardiology, Children's Hospital of Soochow University, 92 Zhongnan Street, Suzhou Industrial Park, Suzhou 215025, Jiangsu, China.
| | - Haitao Lv
- Department of Cardiology, Children's Hospital of Soochow University, 92 Zhongnan Street, Suzhou Industrial Park, Suzhou 215025, Jiangsu, China.
| | - Jian Wang
- Department of Pediatric Surgery, Children's Hospital of Soochow University, 92 Zhongnan Street, Suzhou Industrial Park, Suzhou 215025, Jiangsu, China.
| | - Yiping Shen
- Department of Genetics and Metabolism, Maternal and Child Health Hospital of Guangxi Zhuang Autonomous Region, Nanning 530003, Guangxi, China; Shanghai Children's Medical Center, Shanghai Jiao Tong University School of Medicine, Shanghai 200127, China; Division of Genetics and Genomics, Boston Children's Hospital, Boston, MA, United States; Department of Neurology, Harvard Medical School, 300 Longwood Avenue, Boston, MA 02115, United States.
| | - Hongying Wang
- Department of Clinical Laboratory, Children's Hospital of Soochow University, 92 Zhongnan Street, Suzhou Industrial Park, Suzhou 215025, Jiangsu, China; Department of Clinical Laboratory, Children's Hospital of Wujiang District, Suzhou, 169 Park Road, Wujiang District, Suzhou 215234, Jiangsu, China.
| | - Ling Sun
- Department of Cardiology, Children's Hospital of Soochow University, 92 Zhongnan Street, Suzhou Industrial Park, Suzhou 215025, Jiangsu, China.
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12
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Ferreira CR, Blau N. Clinical and biochemical footprints of inherited metabolic diseases. IV. Metabolic cardiovascular disease. Mol Genet Metab 2021; 132:112-118. [PMID: 33388235 PMCID: PMC7867625 DOI: 10.1016/j.ymgme.2020.12.290] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Revised: 12/16/2020] [Accepted: 12/16/2020] [Indexed: 12/12/2022]
Abstract
Inherited metabolic diseases account for 15-20% of all cases of pediatric cardiomyopathy, with a high mortality of 15-47%. Metabolic diseases can also commonly be associated with other types of cardiovascular involvement such as arrhythmias, valvulopathy or vasculopathy. We reviewed and updated the list of known metabolic etiologies associated with cardiovascular involvement, and found 246 relevant inborn errors of metabolism. This represents the fourth of a series of articles attempting to create and maintain a comprehensive list of clinical and metabolic differential diagnoses according to system involvement.
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Affiliation(s)
- Carlos R Ferreira
- National Human Genome Research Institute, National Institutes of Health, Bethesda, MD, USA.
| | - Nenad Blau
- Division of Metabolism, University Children's Hospital, Zürich, Switzerland.
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13
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Sanford E, Jones MC, Brigger M, Hammer M, Giudugli L, Kingsmore SF, Dimmock D, Bainbridge MN. Postmortem diagnosis of PPA2-associated sudden cardiac death from dried blood spot in a neonate presenting with vocal cord paralysis. Cold Spring Harb Mol Case Stud 2020; 6:mcs.a005611. [PMID: 33028643 PMCID: PMC7552926 DOI: 10.1101/mcs.a005611] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Accepted: 08/12/2020] [Indexed: 01/16/2023] Open
Abstract
Biallelic variants in inorganic pyrophosphatase 2 (PPA2) are known to cause infantile sudden cardiac failure (OMIM #617222), but relatively little is known about phenotypic variability of these patients prior to their death. We report a 5-wk-old male with bilateral vocal cord paralysis and hypertension who had a sudden unexpected cardiac death. Subsequently, molecular autopsy via whole-genome sequencing from newborn dried blood spot identified compound heterozygous mutations in PPA2, with a paternally inherited, pathogenic missense variant (c.514G > A; p.Glu172Lys) and a novel, maternally inherited missense variant of uncertain significance (c.442A > T; p.Thr148Ser). This report expands the presenting phenotype of patients with PPA2 variants. It also highlights the utility of dried blood spots for postmortem molecular diagnosis.
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Affiliation(s)
- Erica Sanford
- Rady Children's Institute of Genomic Medicine, University of California San Diego, La Jolla, California 92093, USA.,Division of Pediatric Critical Care Medicine, Department of Pediatrics, University of California San Diego, La Jolla, California 92093, USA
| | - Marilyn C Jones
- Division of Genetics, Department of Pediatrics, University of California San Diego, La Jolla, California 92093, USA
| | - Matthew Brigger
- Department of Otolaryngology, Rady Children's Hospital, San Diego, California 92123, USA
| | - Monia Hammer
- Rady Children's Institute of Genomic Medicine, University of California San Diego, La Jolla, California 92093, USA
| | - Lucia Giudugli
- Rady Children's Institute of Genomic Medicine, University of California San Diego, La Jolla, California 92093, USA
| | - Stephen F Kingsmore
- Rady Children's Institute of Genomic Medicine, University of California San Diego, La Jolla, California 92093, USA
| | - David Dimmock
- Rady Children's Institute of Genomic Medicine, University of California San Diego, La Jolla, California 92093, USA
| | - Matthew N Bainbridge
- Rady Children's Institute of Genomic Medicine, University of California San Diego, La Jolla, California 92093, USA
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14
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Crandall LG, Lee JH, Friedman D, Lear K, Maloney K, Pinckard JK, Lin P, Andrew T, Roman K, Landi K, Jarrell H, Williamson AK, Downs JCU, Pinneri K, William C, Maleszewski JJ, Reichard RR, Devinsky O. Evaluation of Concordance Between Original Death Certifications and an Expert Panel Process in the Determination of Sudden Unexplained Death in Childhood. JAMA Netw Open 2020; 3:e2023262. [PMID: 33125496 PMCID: PMC7599447 DOI: 10.1001/jamanetworkopen.2020.23262] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
IMPORTANCE The true incidence of sudden unexplained death in childhood (SUDC), already the fifth leading category of death among toddlers by current US Centers for Disease Control and Prevention estimates, is potentially veiled by the varied certification processes by medicolegal investigative offices across the United States. OBJECTIVE To evaluate the frequency of SUDC incidence, understand its epidemiology, and assess the consistency of death certification among medical examiner and coroner offices in the US death investigation system. DESIGN, SETTING, AND PARTICIPANTS In this case series, 2 of 13 forensic pathologists (FPs) conducted masked reviews of 100 cases enrolled in the SUDC Registry and Research Collaborative (SUDCRRC). Children who died aged 11 months to 18 years from 36 US states, Canada, and the United Kingdom had been posthumously enrolled in the SUDCRRC by family members from 2014 to 2017. Comprehensive data from medicolegal investigative offices, clinical offices, and family members were reviewed. Data analysis was conducted from December 2014 to June 2020. MAIN OUTCOMES AND MEASURES Certified cause of death (COD) characterized as explained (accidental or natural) or unexplained, as determined by SUDCRRC masked review process. RESULTS In this study of 100 cases of SUDC (mean [SD] age, 32.1 [31.8] months; 58 [58.0%] boys; 82 [82.0%] White children; 92 [92.0%] from the United States), the original pathologist certified 43 cases (43.0%) as explained COD and 57 (57.0%) as unexplained COD. The SUDCRRC review process led to the following certifications: 16 (16.0%) were explained, 7 (7.0%) were undetermined because of insufficient data, and 77 (77.0%) were unexplained. Experts disagreed with the original COD in 40 cases (40.0%). These data suggest that SUDC incidence is higher than the current Centers for Disease Control and Prevention estimate (ie, 392 deaths in 2018). CONCLUSIONS AND RELEVANCE To our knowledge, this is the first comprehensive masked forensic pathology review process of sudden unexpected pediatric deaths, and it suggests that SUDC may often go unrecognized in US death investigations. Some unexpected pediatric deaths may be erroneously attributed to a natural or accidental COD, negatively affecting surveillance, research, public health funding, and medical care of surviving family members. To further address the challenges of accurate and consistent death certification in SUDC, future studies are warranted.
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Affiliation(s)
| | - Joyce H. Lee
- NYU Grossman School of Medicine, New York, New York
| | | | - Kelly Lear
- Arapahoe County Coroner’s Office, Centennial, Colorado
| | - Katherine Maloney
- Erie County Medical Examiner's Office, Buffalo, New York
- University at Buffalo School of Medicine, Buffalo, New York
| | | | | | - Thomas Andrew
- White Mountain Forensic Consulting Services, Concord, New Hampshire
| | | | | | | | | | | | - Kathy Pinneri
- Montgomery County Forensic Services Department, Conroe, Texas
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15
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Abstract
Mitochondrial diseases are clinically and genetically heterogeneous. These diseases were initially described a little over three decades ago. Limited diagnostic tools created disease descriptions based on clinical, biochemical analytes, neuroimaging, and muscle biopsy findings. This diagnostic mechanism continued to evolve detection of inherited oxidative phosphorylation disorders and expanded discovery of mitochondrial physiology over the next two decades. Limited genetic testing hampered the definitive diagnostic identification and breadth of diseases. Over the last decade, the development and incorporation of massive parallel sequencing has identified approximately 300 genes involved in mitochondrial disease. Gene testing has enlarged our understanding of how genetic defects lead to cellular dysfunction and disease. These findings have expanded the understanding of how mechanisms of mitochondrial physiology can induce dysfunction and disease, but the complete collection of disease-causing gene variants remains incomplete. This article reviews the developments in disease gene discovery and the incorporation of gene findings with mitochondrial physiology. This understanding is critical to the development of targeted therapies.
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Affiliation(s)
- Russell P. Saneto
- Center for Integrative Brain Research, Neuroscience Institute, Seattle, WA 98101, USA
- Department of Neurology/Division of Pediatric Neurology, Seattle Children’s Hospital/University of Washington, Seattle, WA 98105, USA
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16
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Phoon CKL, Halvorsen M, Goldstein DB, Rabin R, Cecchin F, Crandall L, Devinsky O. Sudden unexpected death in asymptomatic infants due to PPA2 variants. Mol Genet Genomic Med 2019; 8:e1008. [PMID: 31705601 PMCID: PMC6978244 DOI: 10.1002/mgg3.1008] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2019] [Revised: 09/04/2019] [Accepted: 09/05/2019] [Indexed: 01/31/2023] Open
Abstract
Background Sudden death in children is a tragic event that often remains unexplained after comprehensive investigation. We report two asymptomatic siblings who died unexpectedly at approximately 1 year of age found to have biallelic (compound heterozygous) variants in PPA2. Methods The index case, parents, and sister were enrolled in the Sudden Unexplained Death in Childhood Registry and Research Collaborative, which included next‐generation genetic screening. Prior published cases of PPA2 variants, along with the known biology of PPA2, were also summarized. Results Whole exome sequencing in both siblings revealed biallelic rare missense variants in PPA2: c.182C > T (p.Ser61Phe) and c.380G > T (p.Arg127Leu). PPA2 encodes a mitochondrially located inorganic pyrophosphatase implicated in progressive and lethal cardiomyopathies. As a regulator and supplier of inorganic phosphate, PPA2 is central to phosphate metabolism. Biological roles include the following: mtDNA maintenance; oxidative phosphorylation and generation of ATP; reactive oxygen species homeostasis; mitochondrial membrane potential regulation; and possibly, retrograde signaling between mitochondria and nucleus. Conclusions Two healthy and asymptomatic sisters died unexpectedly at ages 12 and 10 months, and were diagnosed by molecular autopsy to carry biallelic variants in PPA2. Our cases add additional details to those reported thus far, and broaden the spectrum of clinical and molecular features of PPA2 variants.
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Affiliation(s)
- Colin K L Phoon
- Division of Pediatric Cardiology, New York University School of Medicine, Hassenfeld Children's Hospital at NYU Langone, New York, NY, USA.,Department of Pediatrics, New York University School of Medicine, Hassenfeld Children's Hospital at NYU Langone, New York, NY, USA
| | - Matthew Halvorsen
- Department of Genetics, University of North Carolina, Chapel Hill, NC, USA
| | - David B Goldstein
- Institute for Genomic Medicine, Columbia University Medical Center, New York, NY, USA
| | - Rachel Rabin
- Department of Pediatrics, New York University School of Medicine, Hassenfeld Children's Hospital at NYU Langone, New York, NY, USA
| | - Frank Cecchin
- Division of Pediatric Cardiology, New York University School of Medicine, Hassenfeld Children's Hospital at NYU Langone, New York, NY, USA.,Department of Pediatrics, New York University School of Medicine, Hassenfeld Children's Hospital at NYU Langone, New York, NY, USA
| | - Laura Crandall
- Department of Neurology, New York University School of Medicine, New York, NY, USA
| | - Orrin Devinsky
- Department of Neurology, New York University School of Medicine, New York, NY, USA
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