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Tamayo-Trujillo R, Ibarra-Castillo R, Laso-Bayas JL, Guevara-Ramirez P, Cadena-Ullauri S, Paz-Cruz E, Ruiz-Pozo VA, Doménech N, Ibarra-Rodríguez AA, Zambrano AK. Identifying genomic variant associated with long QT syndrome type 2 in an ecuadorian mestizo individual: a case report. Front Genet 2024; 15:1395012. [PMID: 38957812 PMCID: PMC11217513 DOI: 10.3389/fgene.2024.1395012] [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: 03/02/2024] [Accepted: 05/27/2024] [Indexed: 07/04/2024] Open
Abstract
Introduction Long QT syndrome (LQTS) is an autosomal dominant inherited cardiac condition characterized by a QT interval prolongation and risk of sudden death. There are 17 subtypes of this syndrome associated with genetic variants in 11 genes. The second most common is type 2, caused by a mutation in the KCNH2 gene, which is part of the potassium channel and influences the final repolarization of the ventricular action potential. This case report presents an Ecuadorian teen with congenital Long QT Syndrome type 2 (OMIM ID: 613688), from a family without cardiac diseases or sudden cardiac death backgrounds. Case presentation A 14-year-old girl with syncope, normal echocardiogram, and an irregular electrocardiogram was diagnosed with LQTS. Moreover, by performing Next-Generation Sequencing, a pathogenic variant in the KCNH2 gene p.(Ala614Val) (ClinVar ID: VCV000029777.14) associated with LQTS type 2, and two variants of uncertain significance in the AKAP9 p.(Arg1654GlyfsTer23) (rs779447911), and TTN p. (Arg34653Cys) (ClinVar ID: VCV001475968.4) genes were identified. Furthermore, ancestry analysis showed a mainly Native American proportion. Conclusion Based on the genomic results, the patient was identified to have a high-risk profile, and an implantable cardioverter defibrillator was selected as the best treatment option, highlighting the importance of including both the clinical and genomics aspects for an integral diagnosis.
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Affiliation(s)
- Rafael Tamayo-Trujillo
- Centro de Investigación Genética y Genómica, Facultad de Ciencias de la Salud Eugenio Espejo, Universidad UTE, Quito, Ecuador
| | | | | | - Patricia Guevara-Ramirez
- Centro de Investigación Genética y Genómica, Facultad de Ciencias de la Salud Eugenio Espejo, Universidad UTE, Quito, Ecuador
| | - Santiago Cadena-Ullauri
- Centro de Investigación Genética y Genómica, Facultad de Ciencias de la Salud Eugenio Espejo, Universidad UTE, Quito, Ecuador
| | - Elius Paz-Cruz
- Centro de Investigación Genética y Genómica, Facultad de Ciencias de la Salud Eugenio Espejo, Universidad UTE, Quito, Ecuador
| | - Viviana A. Ruiz-Pozo
- Centro de Investigación Genética y Genómica, Facultad de Ciencias de la Salud Eugenio Espejo, Universidad UTE, Quito, Ecuador
| | - Nieves Doménech
- Instituto de Investigación Biomédica de A Coruña (INIBIC)-CIBERCV, Complexo Hospitalario Universitario de A Coruña (CHUAC), Sergas. Universidad da Coruña (UDC), Coruña, Spain
| | - Adriana Alexandra Ibarra-Rodríguez
- Grupo de investigación identificación Genética-IdentiGEN, Facultad de Ciencias Exactas y Naturales (FCEN), Universidad de Antioquia, Medellín, Colombia
| | - Ana Karina Zambrano
- Centro de Investigación Genética y Genómica, Facultad de Ciencias de la Salud Eugenio Espejo, Universidad UTE, Quito, Ecuador
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Erdogan M, Sunkak S, Bahadır O, Doğan ME, Ada Y, Balta B. A Novel Variant in AKAP9 Gene, a Controversial Gene, in Long QT Syndrome. Mol Syndromol 2024; 15:136-142. [PMID: 38585551 PMCID: PMC10996337 DOI: 10.1159/000534624] [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: 08/05/2023] [Accepted: 10/14/2023] [Indexed: 04/09/2024] Open
Abstract
Introduction Long QT syndrome (LQTS) is a common congenital cause of fatal cardiac arrhythmia. Characteristic clinical findings are prolonged QT interval and ventricular arrhythmia on electrocardiogram (ECG), syncope, seizure, and sudden death. It is a genetically heterogeneous disease. To date, disease-causing variant have been reported in seventeen genes. The AKAP9 is still considered controversial among those genes. Case Report We report the case of a 10-year-old female who was born from a non-consanguineous Turkish couple. She visited pediatrics cardiology clinic presenting with dyspnea and tachycardia. Prolongation of the QT interval was detected in her ECG. Panel test associated with LQTS genes was performed. She was diagnosed with long QTS type 11 due to a heterozygous variant in AKAP9:c.11487_11489 delTACinsCGTA, p.(Thr3830ValfsTer12), that was revealed through next-generation sequencing test. The variant was also found in her mother and brother. Discussion and Conclusion Novel heterozygous frameshift variant in the AKAP9 gene was considered as "Uncertain Significance (VUS)" in the ACMG classification. The novel variant is absent from population databases (PM2); it is a null variant (PVS1_moderate). AKAP9 gene has the lowest known rate among the causes of LQTS. Information is limited on genotype-phenotype correlation. Yet it is still among the candidate genes. Although the relationship of the AKAP9 gene with LQTS has not yet been fully indicated, individuals with a pathogenic variant in AKAP9 gene and silent carriers may be at risk for fatal cardiac events. Improvements of the genetic tests in the near future may contribute to the literature and clinical research about AKAP9 gene.
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Affiliation(s)
- Murat Erdogan
- Department of Medical Genetics, Kayseri City Hospital, Kayseri, Turkey
| | - Suleyman Sunkak
- Departments of Pediatrics, Department of Pediatrics Cardiology, Kayseri City Hospital, Kayseri, Turkey
| | | | | | - Yasin Ada
- Department of Medical Genetics, Kayseri City Hospital, Kayseri, Turkey
| | - Burhan Balta
- Department of Medical Genetics, Kayseri City Hospital, Kayseri, Turkey
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Lerman BB, Markowitz SM, Cheung JW, Thomas G, Ip JE. Ventricular Tachycardia Due to Triggered Activity: Role of Early and Delayed Afterdepolarizations. JACC Clin Electrophysiol 2024; 10:379-401. [PMID: 38127010 DOI: 10.1016/j.jacep.2023.10.033] [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: 06/22/2023] [Revised: 10/24/2023] [Accepted: 10/28/2023] [Indexed: 12/23/2023]
Abstract
Most forms of sustained ventricular tachycardia (VT) are caused by re-entry, resulting from altered myocardial conduction and refractoriness secondary to underlying structural heart disease. In contrast, VT caused by triggered activity (TA) is unrelated to an abnormal structural substrate and is often caused by molecular defects affecting ion channel function or regulation of intracellular calcium cycling. This review summarizes the cellular and molecular bases underlying TA and exemplifies their clinical relevance with selective representative scenarios. The underlying basis of TA caused by delayed afterdepolarizations is related to sarcoplasmic reticulum calcium overload, calcium waves, and diastolic sarcoplasmic reticulum calcium leak. Clinical examples of TA caused by delayed afterdepolarizations include sustained right and left ventricular outflow tract tachycardia and catecholaminergic polymorphic VT. The other form of afterpotentials, early afterdepolarizations, are systolic events and inscribe early afterdepolarizations during phase 2 or phase 3 of the action potential. The fundamental defect is a decrease in repolarization reserve with associated increases in late plateau inward currents. Malignant ventricular arrhythmias in the long QT syndromes are initiated by early afterdepolarization-mediated TA. An understanding of the molecular and cellular bases of these arrhythmias has resulted in generally effective pharmacologic-based therapies, but these are nonspecific agents that have off-target effects. Therapeutic efficacy may need to be augmented with an implantable defibrillator. Next-generation therapies will include novel agents that rescue arrhythmogenic abnormalities in cellular signaling pathways and gene therapy approaches that transfer or edit pathogenic gene variants or silence mutant messenger ribonucleic acid.
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Affiliation(s)
- Bruce B Lerman
- Department of Medicine, Division of Cardiology and the Greenberg Institute for Cardiac Electrophysiology, Department of Medicine, Cornell University Medical Center, New York, New York, USA.
| | - Steven M Markowitz
- Department of Medicine, Division of Cardiology and the Greenberg Institute for Cardiac Electrophysiology, Department of Medicine, Cornell University Medical Center, New York, New York, USA
| | - Jim W Cheung
- Department of Medicine, Division of Cardiology and the Greenberg Institute for Cardiac Electrophysiology, Department of Medicine, Cornell University Medical Center, New York, New York, USA
| | - George Thomas
- Department of Medicine, Division of Cardiology and the Greenberg Institute for Cardiac Electrophysiology, Department of Medicine, Cornell University Medical Center, New York, New York, USA
| | - James E Ip
- Department of Medicine, Division of Cardiology and the Greenberg Institute for Cardiac Electrophysiology, Department of Medicine, Cornell University Medical Center, New York, New York, USA
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Copier JS, Bootsma M, Ng CA, Wilde AAM, Bertels RA, Bikker H, Christiaans I, van der Crabben SN, Hol JA, Koopmann TT, Knijnenburg J, Lommerse AAJ, van der Smagt JJ, Bezzina CR, Vandenberg JI, Verkerk AO, Barge-Schaapveld DQCM, Lodder EM. Reclassification of a likely pathogenic Dutch founder variant in KCNH2; implications of reduced penetrance. Hum Mol Genet 2023; 32:1072-1082. [PMID: 36269083 PMCID: PMC10026256 DOI: 10.1093/hmg/ddac261] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2022] [Revised: 10/03/2022] [Accepted: 10/14/2022] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Variants in KCNH2, encoding the human ether a-go-go (hERG) channel that is responsible for the rapid component of the cardiac delayed rectifier K+ current (IKr), are causal to long QT syndrome type 2 (LQTS2). We identified eight index patients with a new variant of unknown significance (VUS), KCNH2:c.2717C > T:p.(Ser906Leu). We aimed to elucidate the biophysiological effect of this variant, to enable reclassification and consequent clinical decision-making. METHODS A genotype-phenotype overview of the patients and relatives was created. The biophysiological effects were assessed independently by manual-, and automated calibrated patch clamp. HEK293a cells expressing (i) wild-type (WT) KCNH2, (ii) KCNH2-p.S906L alone (homozygous, Hm) or (iii) KCNH2-p.S906L in combination with WT (1:1) (heterozygous, Hz) were used for manual patching. Automated patch clamp measured the variants function against known benign and pathogenic variants, using Flp-In T-rex HEK293 KCNH2-variant cell lines. RESULTS Incomplete penetrance of LQTS2 in KCNH2:p.(Ser906Leu) carriers was observed. In addition, some patients were heterozygous for other VUSs in CACNA1C, PKP2, RYR2 or AKAP9. The phenotype of carriers of KCNH2:p.(Ser906Leu) ranged from asymptomatic to life-threatening arrhythmic events. Manual patch clamp showed a reduced current density by 69.8 and 60.4% in KCNH2-p.S906L-Hm and KCNH2-p.S906L-Hz, respectively. The time constant of activation was significantly increased with 80.1% in KCNH2-p.S906L-Hm compared with KCNH2-WT. Assessment of KCNH2-p.S906L-Hz by calibrated automatic patch clamp assay showed a reduction in current density by 35.6%. CONCLUSION The reduced current density in the KCNH2-p.S906L-Hz indicates a moderate loss-of-function. Combined with the reduced penetrance and variable phenotype, we conclude that KCNH2:p.(Ser906Leu) is a low penetrant likely pathogenic variant for LQTS2.
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Affiliation(s)
- Jaël S Copier
- Experimental Cardiology, Amsterdam UMC location University of Amsterdam, Meibergdreef 9, Amsterdam, The Netherlands
- Amsterdam Cardiovascular Sciences, Heart Failure & Arrhythmias, Amsterdam, The Netherlands
- European Reference Network for Rare, Low Prevalence and Complex Diseases of the Heart: ERN GUARD-Heart'
| | - Marianne Bootsma
- Department of Cardiology, Leiden University Medical Center, Albinusdreef 2, 2300 Leiden, The Netherlands
| | - Chai A Ng
- Mark Cowley Lidwill Research Program in Cardiac Electrophysiology, Victor Chang Cardiac Research Institute, Darlinghurst, New South Wales, Australia
- School of Clinical Medicine, UNSW Sydney, Darlinghurst, New South Wales, Australia
| | - Arthur A M Wilde
- Experimental Cardiology, Amsterdam UMC location University of Amsterdam, Meibergdreef 9, Amsterdam, The Netherlands
- Amsterdam Cardiovascular Sciences, Heart Failure & Arrhythmias, Amsterdam, The Netherlands
- European Reference Network for Rare, Low Prevalence and Complex Diseases of the Heart: ERN GUARD-Heart'
| | - Robin A Bertels
- Department of Paediatric Cardiology, Leiden University Medical Center, Willem-Alexander Children's Hospital, Albinusdreef 2, 2333 Leiden, Netherlands
| | - Hennie Bikker
- European Reference Network for Rare, Low Prevalence and Complex Diseases of the Heart: ERN GUARD-Heart'
- Human Genetics, Amsterdam UMC location University of Amsterdam, Meibergdreef 9, Amsterdam, The Netherlands
| | - Imke Christiaans
- Department of Clinical Genetics, University Medical Centre Groningen, 9713GZ Groningen, The Netherlands
| | - Saskia N van der Crabben
- Human Genetics, Amsterdam UMC location University of Amsterdam, Meibergdreef 9, Amsterdam, The Netherlands
| | - Janna A Hol
- Erasmus MC, Clinical Genetics, Doctor Molewaterplein 40, 3015 Rotterdam, The Netherlands
| | - Tamara T Koopmann
- Clinical Genetics, Leiden University Medical Center, Albinusdreef 2, 2333 Leiden, The Netherlands
| | - Jeroen Knijnenburg
- Clinical Genetics, Leiden University Medical Center, Albinusdreef 2, 2333 Leiden, The Netherlands
| | - Aafke A J Lommerse
- Department of Cardiology, Leiden University Medical Center, Albinusdreef 2, 2300 Leiden, The Netherlands
| | - Jasper J van der Smagt
- Clinical Genetics, University Medical Center Utrecht, Lundlaan 6, Utrecht, The Netherlands
| | - Connie R Bezzina
- Experimental Cardiology, Amsterdam UMC location University of Amsterdam, Meibergdreef 9, Amsterdam, The Netherlands
- Amsterdam Cardiovascular Sciences, Heart Failure & Arrhythmias, Amsterdam, The Netherlands
- European Reference Network for Rare, Low Prevalence and Complex Diseases of the Heart: ERN GUARD-Heart'
| | - Jamie I Vandenberg
- Mark Cowley Lidwill Research Program in Cardiac Electrophysiology, Victor Chang Cardiac Research Institute, Darlinghurst, New South Wales, Australia
- School of Clinical Medicine, UNSW Sydney, Darlinghurst, New South Wales, Australia
| | - Arie O Verkerk
- Experimental Cardiology, Amsterdam UMC location University of Amsterdam, Meibergdreef 9, Amsterdam, The Netherlands
- Amsterdam Cardiovascular Sciences, Heart Failure & Arrhythmias, Amsterdam, The Netherlands
- European Reference Network for Rare, Low Prevalence and Complex Diseases of the Heart: ERN GUARD-Heart'
- Medical Biology, Amsterdam UMC location University of Amsterdam, Meibergdreef 9, Amsterdam, The Netherlands
| | | | - Elisabeth M Lodder
- Experimental Cardiology, Amsterdam UMC location University of Amsterdam, Meibergdreef 9, Amsterdam, The Netherlands
- Amsterdam Cardiovascular Sciences, Heart Failure & Arrhythmias, Amsterdam, The Netherlands
- European Reference Network for Rare, Low Prevalence and Complex Diseases of the Heart: ERN GUARD-Heart'
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Schwartz PJ, Sala L. The impact of genetics on the long QT syndrome: myth or reality? Curr Opin Cardiol 2023; 38:149-156. [PMID: 36789771 DOI: 10.1097/hco.0000000000001027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
PURPOSE OF REVIEW To summarize and critically assess the contribution of genetics to the Long QT Syndrome (LQTS), with specific reference to the unraveling of its underlying mechanisms and to its impact on clinical practice. RECENT FINDINGS The evolution towards our current approach to therapy for LQTS patients is examined in terms of risk stratification, gene-specific management, and assessment of the clinical impact that genetic modifiers may have in modulating the natural history of the patients. Glimpses are provided on the newest multidisciplinary approaches to study disease mechanisms, test new candidate drugs and identify precision treatments. SUMMARY It is undeniable that genetics has revolutionized our mechanistic understanding of cardiac channelopathies. Its impact has been enormous but, curiously, the way LQTS patients are being treated today is largely the same that was used in the pregenetic era, even though management has been refined and gene-specific differences allow a more individually tailored antiarrhythmic protection. The synergy of genetic findings with modern in vitro and in silico tools may expand precision treatments; however, they will need to prove more effective than the current therapeutic approaches and equally safe.
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Affiliation(s)
- Peter J Schwartz
- Istituto Auxologico Italiano IRCCS, Center for Cardiac Arrhythmias of Genetic Origin and Laboratory of Cardiovascular Genetics
| | - Luca Sala
- Istituto Auxologico Italiano IRCCS, Center for Cardiac Arrhythmias of Genetic Origin and Laboratory of Cardiovascular Genetics.,Department of Biotechnology and Biosciences, University of Milano - Bicocca, Milan, Italy
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6
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Vaiman EE, Shnayder NA, Zhuravlev NM, Petrova MM, Asadullin AR, Al-Zamil M, Garganeeva NP, Shipulin GA, Cumming P, Nasyrova RF. Genetic Biomarkers of Antipsychotic-Induced Prolongation of the QT Interval in Patients with Schizophrenia. Int J Mol Sci 2022; 23:ijms232415786. [PMID: 36555428 PMCID: PMC9785058 DOI: 10.3390/ijms232415786] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Revised: 12/07/2022] [Accepted: 12/07/2022] [Indexed: 12/14/2022] Open
Abstract
Antipsychotics (AP) induced prolongation of the QT interval in patients with schizophrenia (Sch) is an actual interdisciplinary problem as it increases the risk of sudden death syndrome. Long QT syndrome (LQTS) as a cardiac adverse drug reaction is a multifactorial symptomatic disorder, the development of which is influenced by modifying factors (APs' dose, duration of APs therapy, APs polytherapy, and monotherapy, etc.) and non-modifying factors (genetic predisposition, gender, age, etc.). The genetic predisposition to AP-induced LQTS may be due to several causes, including causal mutations in the genes responsible for monoheme forms of LQTS, single nucleotide variants (SNVs) of the candidate genes encoding voltage-dependent ion channels expressed both in the brain and in the heart, and SNVs of candidate genes encoding key enzymes of APs metabolism. This narrative review summarizes the results of genetic studies on AP-induced LQTS and proposes a new personalized approach to assessing the risk of its development (low, moderate, high). We recommend implementation in protocols of primary diagnosis of AP-induced LQTS and medication dispensary additional observations of the risk category of patients receiving APs, deoxyribonucleic acid profiling, regular electrocardiogram monitoring, and regular therapeutic drug monitoring of the blood APs levels.
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Affiliation(s)
- Elena E. Vaiman
- Institute of Personalized Psychiatry and Neurology, V. M. Bekhterev National Medical Research Centre for Psychiatry and Neurology, 192019 Saint Petersburg, Russia
| | - Natalia A. Shnayder
- Institute of Personalized Psychiatry and Neurology, V. M. Bekhterev National Medical Research Centre for Psychiatry and Neurology, 192019 Saint Petersburg, Russia
- Shared Core Facilities “Molecular and Cell Technologies”, V. F. Voyno-Yasenetsky Krasnoyarsk State Medical University, 660022 Krasnoyarsk, Russia
- Correspondence: (N.A.S.); (R.F.N.); Tel.: +7-(812)-670-02-20 (N.A.S. & R.F.N.)
| | - Nikita M. Zhuravlev
- Institute of Personalized Psychiatry and Neurology, V. M. Bekhterev National Medical Research Centre for Psychiatry and Neurology, 192019 Saint Petersburg, Russia
| | - Marina M. Petrova
- Shared Core Facilities “Molecular and Cell Technologies”, V. F. Voyno-Yasenetsky Krasnoyarsk State Medical University, 660022 Krasnoyarsk, Russia
| | - Azat R. Asadullin
- Department of Psychiatry and Addiction, Bashkir State Medical University, 450008 Ufa, Russia
| | - Mustafa Al-Zamil
- Department of Physiotherapy, Faculty of Continuing Medical Education, Peoples’ Friendship University of Russia, 117198 Moscow, Russia
| | - Natalia P. Garganeeva
- Department of General Medical Practice and Outpatient Therapy, Siberian State Medical University, 634050 Tomsk, Russia
| | - German A. Shipulin
- Centre for Strategic Planning and Management of Biomedical Health Risks Management, 119121 Moscow, Russia
| | - Paul Cumming
- Department of Nuclear Medicine, Bern University Hospital, 3010 Bern, Switzerland
- School of Psychology and Counselling, Queensland University of Technology, Brisbane 4000, Australia
| | - Regina F. Nasyrova
- Institute of Personalized Psychiatry and Neurology, V. M. Bekhterev National Medical Research Centre for Psychiatry and Neurology, 192019 Saint Petersburg, Russia
- International Centre for Education and Research in Neuropsychiatry, Samara State Medical University, 443016 Samara, Russia
- Correspondence: (N.A.S.); (R.F.N.); Tel.: +7-(812)-670-02-20 (N.A.S. & R.F.N.)
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Reprogramming of a human induced pluripotent stem cell line (ZZUSAHi004-A) from a long QT syndrome patient with a heterozygous AKAP9 (c. 4021C > A) mutant. Stem Cell Res 2022; 65:102966. [PMID: 36395689 DOI: 10.1016/j.scr.2022.102966] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/08/2022] [Accepted: 11/08/2022] [Indexed: 11/13/2022] Open
Abstract
Long QT syndrome is one of the most common hereditary arrhythmias in clinic. Mutations in AKAP9 gene can lead to long QT syndrome type 11 (LQT11). In this study, a human induced pluripotent stem cell line ZZUSAHi004-A from a 3-year-old male patient with long QT syndrome carrying a heterozygous mutation in AKAP9 gene using non-integrative Sendai viral reprogramming technology. ZZUSAHi004-A showed normal male karyotype (46, XY), expressed pluripotency markers and could differentiate into all three germ layers in vitro. ZZUSAHi004-A can serve as a cell disease model in the understanding of LQT11 pathogenesis.
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Postrigan AE, Babushkina NP, Svintsova LI, Plotnikova IV, Skryabin NA. Clinical and Genetic Characteristics of Congenital Long QT Syndrome. RUSS J GENET+ 2022. [DOI: 10.1134/s1022795422100064] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Corrado D, Link MS, Schwartz PJ. Implantable defibrillators in primary prevention of genetic arrhythmias. A shocking choice? Eur Heart J 2022; 43:3029-3040. [PMID: 35725934 PMCID: PMC9443985 DOI: 10.1093/eurheartj/ehac298] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Revised: 03/10/2022] [Accepted: 05/24/2022] [Indexed: 12/15/2022] Open
Abstract
Many previously unexplained life-threatening ventricular arrhythmias and sudden cardiac deaths (SCDs) in young individuals are now recognized to be genetic in nature and are ascribed to a growing number of distinct inherited arrhythmogenic diseases. These include hypertrophic cardiomyopathy, arrhythmogenic cardiomyopathy, long QT syndrome, Brugada syndrome, catecholaminergic polymorphic ventricular tachycardia (VT), and short QT syndrome. Because of their lower frequency compared to coronary disease, risk factors for SCD are not very precise in patients with inherited arrhythmogenic diseases. As randomized studies are generally non-feasible and may even be ethically unjustifiable, especially in the presence of effective therapies, the risk assessment of malignant arrhythmic events such as SCD, cardiac arrest due to ventricular fibrillation (VF), appropriate implantable cardioverter defibrillator (ICD) interventions, or ICD therapy on fast VT/VF to guide ICD implantation is based on observational data and expert consensus. In this document, we review risk factors for SCD and indications for ICD implantation and additional therapies. What emerges is that, allowing for some important differences between cardiomyopathies and channelopathies, there is a growing and disquieting trend to create, and then use, semi-automated systems (risk scores, risk calculators, and, to some extent, even guidelines) which then dictate therapeutic choices. Their common denominator is a tendency to favour ICD implantation, sometime with reason, sometime without it. This contrasts with the time-honoured approach of selecting, among the available therapies, the best option (ICDs included) based on the clinical judgement for the specific patient and after having assessed the protection provided by optimal medical treatment.
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Affiliation(s)
- Domenico Corrado
- Inherited Arrhythmogenic Cardiomyopathies and Sports Cardiology Unit, Department of Cardiac, Thoracic and Vascular Sciences, University of Padova Medical School, Padova, Italy
| | - Mark S Link
- Division of Cardiology, University of Texas Southwestern Medical Center, Dallas, USA
| | - Peter J Schwartz
- Istituto Auxologico Italiano, IRCCS, Center for Cardiac Arrhythmias of Genetic Origin and Laboratory of Cardiovascular Genetics, Milan, Italy
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Wang M, Tu X. The Genetics and Epigenetics of Ventricular Arrhythmias in Patients Without Structural Heart Disease. Front Cardiovasc Med 2022; 9:891399. [PMID: 35783865 PMCID: PMC9240357 DOI: 10.3389/fcvm.2022.891399] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2022] [Accepted: 05/25/2022] [Indexed: 12/19/2022] Open
Abstract
Ventricular arrhythmia without structural heart disease is an arrhythmic disorder that occurs in structurally normal heart and no transient or reversible arrhythmia factors, such as electrolyte disorders and myocardial ischemia. Ventricular arrhythmias without structural heart disease can be induced by multiple factors, including genetics and environment, which involve different genetic and epigenetic regulation. Familial genetic analysis reveals that cardiac ion-channel disorder and dysfunctional calcium handling are two major causes of this type of heart disease. Genome-wide association studies have identified some genetic susceptibility loci associated with ventricular tachycardia and ventricular fibrillation, yet relatively few loci associated with no structural heart disease. The effects of epigenetics on the ventricular arrhythmias susceptibility genes, involving non-coding RNAs, DNA methylation and other regulatory mechanisms, are gradually being revealed. This article aims to review the knowledge of ventricular arrhythmia without structural heart disease in genetics, and summarizes the current state of epigenetic regulation.
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Song Y, Zheng Z, Lian J. Deciphering Common Long QT Syndrome Using CRISPR/Cas9 in Human-Induced Pluripotent Stem Cell-Derived Cardiomyocytes. Front Cardiovasc Med 2022; 9:889519. [PMID: 35647048 PMCID: PMC9136094 DOI: 10.3389/fcvm.2022.889519] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2022] [Accepted: 04/22/2022] [Indexed: 11/13/2022] Open
Abstract
From carrying potentially pathogenic genes to severe clinical phenotypes, the basic research in the inherited cardiac ion channel disease such as long QT syndrome (LQTS) has been a significant challenge in explaining gene-phenotype heterogeneity. These have opened up new pathways following the parallel development and successful application of stem cell and genome editing technologies. Stem cell-derived cardiomyocytes and subsequent genome editing have allowed researchers to introduce desired genes into cells in a dish to replicate the disease features of LQTS or replace causative genes to normalize the cellular phenotype. Importantly, this has made it possible to elucidate potential genetic modifiers contributing to clinical heterogeneity and hierarchically manage newly identified variants of uncertain significance (VUS) and more therapeutic options to be tested in vitro. In this paper, we focus on and summarize the recent advanced application of human-induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) combined with clustered regularly interspaced short palindromic repeats/CRISPR-associated system 9 (CRISPR/Cas9) in the interpretation for the gene-phenotype relationship of the common LQTS and presence challenges, increasing our understanding of the effects of mutations and the physiopathological mechanisms in the field of cardiac arrhythmias.
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Affiliation(s)
- Yongfei Song
- Department of Cardiovascular, Ningbo Institute of Innovation for Combined Medicine and Engineering, Ningbo, China
- Yongfei Song
| | - Zequn Zheng
- Department of Cardiovascular, Medical College, Ningbo University, Ningbo, China
- Department of Cardiovascular, Lihuili Hospital Affiliated to Ningbo University, Ningbo, China
| | - Jiangfang Lian
- Department of Cardiovascular, Ningbo Institute of Innovation for Combined Medicine and Engineering, Ningbo, China
- Department of Cardiovascular, Medical College, Ningbo University, Ningbo, China
- Department of Cardiovascular, Lihuili Hospital Affiliated to Ningbo University, Ningbo, China
- *Correspondence: Jiangfang Lian
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12
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Wang Y, Zuo C, Wang X, Xiao Y, Liu Q, Chen Z. Frequent torsades de pointes in a child with novel AKAP9 mutation: A case report and literature review. Front Pediatr 2022; 10:1027177. [PMID: 36699290 PMCID: PMC9869367 DOI: 10.3389/fped.2022.1027177] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/24/2022] [Accepted: 12/12/2022] [Indexed: 01/11/2023] Open
Abstract
INTRODUCTION The aim of the present study is to report the diagnosis and treatment of a rare case of frequent torsades de pointes (Tdp) in a child with a novel AKAP9 mutation. A 13-year-old girl suffered from repeated syncope and frequent Tdp. An electrocardiogram (ECG) showed frequent multisource premature ventricular contractions with the R-ON-T phenomenon. The QTc ranged from 410 to 468 ms. The genetic test indicated a heterozygous mutation, namely, c.11714T > C (p.M3905T), in the AKAP9 gene, which is a controversial gene in long QT syndrome. After treatment with propranolol, recurrent syncope occurred, and the patient received an implantable cardioverter defibrillator (ICD). Due to frequent electrical storms at home, the child was additionally treated with propafenone to prevent arrhythmia. The antitachycardia pacing (ATP) function in the ICD was turned off, and the threshold of ventricular tachycardia (VT) assessment was adjusted from 180 beats/min to 200 beats/min. The patient was followed up for 12 months without malignant arrhythmia and electric shock. CONCLUSION Genetic testing may be a useful tool to determine the origin of channelopathy, but the results should be interpreted in combination with the actual situation. Rational parameter settings for the ICD and application of antiarrhythmic drugs can reduce the mortality rates of children.
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Affiliation(s)
- Yefeng Wang
- Department of Cardiology, Hunan Children's Hospital, Changsha, China
| | - Chao Zuo
- Department of Cardiology, Hunan Children's Hospital, Changsha, China
| | - Xiang Wang
- Department of Cardiology, Hunan Children's Hospital, Changsha, China
| | - Yunbin Xiao
- Department of Cardiology, Hunan Children's Hospital, Changsha, China
| | - Qiming Liu
- Department of Cardiology, Second Xiangya Hospital, Central South University, Changsha, China
| | - Zhi Chen
- Department of Cardiology, Hunan Children's Hospital, Changsha, China
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13
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Accurate interpretation of genetic variants in sudden unexpected death in infancy by trio-targeted gene-sequencing panel analysis. Sci Rep 2021; 11:21532. [PMID: 34728707 PMCID: PMC8563990 DOI: 10.1038/s41598-021-00962-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Accepted: 10/20/2021] [Indexed: 12/18/2022] Open
Abstract
In sudden unexpected death in infancy cases, postmortem genetic analysis with next-generation sequencing potentially can extract candidate genes associated with sudden death. However, it is difficult to accurately interpret the clinically significant genetic variants. The study aim was to conduct trio analysis of cases of sudden unexpected death in infancy and their parents to more accurately interpret the clinically significant disease-associated gene variants associated with cause of death. From the TruSight One panel targeting 4813 genes we extracted candidate genetic variants of 66 arrhythmia-, 63 inherited metabolic disease-, 81 mitochondrial disease-, and 6 salt-losing tubulopathy-related genes in 7 cases and determined if they were de novo or parental-derived variants. Thirty-four parental-derived variants and no de novo variants were found, but none appeared to be related to the cause of death. Using trio analysis and an in silico algorithm to analyze all 4813 genes, we identified OBSCN of compound heterozygous and HCCS of hemizygous variants as new candidate genetic variants related to cause of death. Genetic analysis of these deceased infants and their living parents can provide more accurate interpretation of the clinically significant genetic variants than previously possible and help confirm the cause of death.
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14
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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: 25] [Impact Index Per Article: 8.3] [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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15
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Crotti L, Odening KE, Sanguinetti MC. Heritable arrhythmias associated with abnormal function of cardiac potassium channels. Cardiovasc Res 2021; 116:1542-1556. [PMID: 32227190 DOI: 10.1093/cvr/cvaa068] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Revised: 02/24/2020] [Accepted: 03/26/2020] [Indexed: 12/16/2022] Open
Abstract
Cardiomyocytes express a surprisingly large number of potassium channel types. The primary physiological functions of the currents conducted by these channels are to maintain the resting membrane potential and mediate action potential repolarization under basal conditions and in response to changes in the concentrations of intracellular sodium, calcium, and ATP/ADP. Here, we review the diversity and functional roles of cardiac potassium channels under normal conditions and how heritable mutations in the genes encoding these channels can lead to distinct arrhythmias. We briefly review atrial fibrillation and J-wave syndromes. For long and short QT syndromes, we describe their genetic basis, clinical manifestation, risk stratification, traditional and novel therapeutic approaches, as well as insights into disease mechanisms provided by animal and cellular models.
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Affiliation(s)
- Lia Crotti
- Center for Cardiac Arrhythmias of Genetic Origin, Istituto Auxologico Italiano, IRCCS, Milan, Italy.,Laboratory of Cardiovascular Genetics, Istituto Auxologico Italiano, IRCCS, Milan, Italy.,Department of Cardiovascular, Neural and Metabolic Sciences, Istituto Auxologico Italiano, IRCCS, San Luca Hospital, Milan, Italy.,Department of Medicine and Surgery, University of Milano-Bicocca, Milan, Italy
| | - Katja E Odening
- Department of Cardiology and Angiology I, Heart Center University of Freiburg, Medical Faculty, Freiburg, Germany.,Institute of Experimental Cardiovascular Medicine, Heart Center University of Freiburg, Medical Faculty, Freiburg, Germany.,Department of Cardiology, Translational Cardiology, Inselspital, Bern University Hospital, and Institute of Physiology, University of Bern, Bern, Switzerland
| | - Michael C Sanguinetti
- Department of Internal Medicine, Nora Eccles Harrison Cardiovascular Research and Training Institute, University of Utah, Salt Lake City, UT, USA
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16
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Monasky MM, Rutigliani C, Micaglio E, Pappone C. Commentary: Peptide-Based Targeting of the L-Type Calcium Channel Corrects the Loss-of-Function Phenotype of Two Novel Mutations of the CACNA1 Gene Associated With Brugada Syndrome. Front Physiol 2021; 12:682567. [PMID: 34177625 PMCID: PMC8220137 DOI: 10.3389/fphys.2021.682567] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Accepted: 05/10/2021] [Indexed: 01/27/2023] Open
Affiliation(s)
- Michelle M Monasky
- Arrhythmology Department, IRCCS Policlinico San Donato, San Donato Milanese, Milan, Italy
| | | | - Emanuele Micaglio
- Arrhythmology Department, IRCCS Policlinico San Donato, San Donato Milanese, Milan, Italy
| | - Carlo Pappone
- Arrhythmology Department, IRCCS Policlinico San Donato, San Donato Milanese, Milan, Italy.,Vita-Salute San Raffaele University, Milan, Italy
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17
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Schwartz PJ. 1970-2020: 50 years of research on the long QT syndrome-from almost zero knowledge to precision medicine. Eur Heart J 2021; 42:1063-1072. [PMID: 33057695 DOI: 10.1093/eurheartj/ehaa769] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Revised: 07/13/2020] [Accepted: 09/07/2020] [Indexed: 12/17/2022] Open
Abstract
To those of us involved in clinical research it seldom happens to begin working on a rather obscure disease, still largely unexplored, and to follow its ripening into a medical entity of large interest to clinicians and basic scientists alike, and moreover to do so for exactly 50 years. This is what has been my privilege in the relentless pursuit of the intriguing disease known as the long QT syndrome (LQTS). This essay begins with the encounter with my first patient affected by LQTS when just a handful of cardiologists had seen similar cases and continues with the series of efforts, some sound some amateurish, which eventually led-together with many brilliant partners and associates-to describe and understand the natural history of the disease and the most effective therapies. It then touches on how our International Registry for LQTS, with its well-documented family trees, constituted the necessary springboard for the major genetic discoveries of the 1990s. From the explosion of genetic data, my own interest focused first on the intriguing genotype-phenotype correlation and then on 'modifier genes', in the attempt of understanding why family members with the same disease-causing mutation could have an opposite clinical history. And from there on to iPS-derived cardiomyocytes, used to unravelling the specific mechanisms of action of modifier genes and to exploring novel therapeutic strategies. This long, and highly rewarding, journey continues because the fascination and the attraction of the unknown are irresistible.
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Affiliation(s)
- Peter J Schwartz
- Istituto Auxologico Italiano, IRCCS, Center for Cardiac Arrhythmias of Genetic Origin and Laboratory of Cardiovascular Genetics, Via Pier Lombardo, 22, Milan 20135, Italy
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18
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Tse G, Lee S, Zhou J, Liu T, Wong ICK, Mak C, Mok NS, Jeevaratnam K, Zhang Q, Cheng SH, Wong WT. Territory-Wide Chinese Cohort of Long QT Syndrome: Random Survival Forest and Cox Analyses. Front Cardiovasc Med 2021; 8:608592. [PMID: 33614747 PMCID: PMC7892622 DOI: 10.3389/fcvm.2021.608592] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Accepted: 01/11/2021] [Indexed: 01/20/2023] Open
Abstract
Introduction: Congenital long QT syndrome (LQTS) is a cardiac ion channelopathy that predisposes affected individuals to spontaneous ventricular tachycardia/fibrillation (VT/VF) and sudden cardiac death (SCD). The main aims of the study were to: (1) provide a description of the local epidemiology of LQTS, (2) identify significant risk factors of ventricular arrhythmias in this cohort, and (3) compare the performance of traditional Cox regression with that of random survival forests. Methods: This was a territory-wide retrospective cohort study of patients diagnosed with congenital LQTS between 1997 and 2019. The primary outcome was spontaneous VT/VF. Results: This study included 121 patients [median age of initial presentation: 20 (interquartile range: 8-44) years, 62% female] with a median follow-up of 88 (51-143) months. Genetic analysis identified novel mutations in KCNQ1, KCNH2, SCN5A, ANK2, CACNA1C, CAV3, and AKAP9. During follow-up, 23 patients developed VT/VF. Univariate Cox regression analysis revealed that age [hazard ratio (HR): 1.02 (1.01-1.04), P = 0.007; optimum cut-off: 19 years], presentation with syncope [HR: 3.86 (1.43-10.42), P = 0.008] or VT/VF [HR: 3.68 (1.62-8.37), P = 0.002] and the presence of PVCs [HR: 2.89 (1.22-6.83), P = 0.015] were significant predictors of spontaneous VT/VF. Only initial presentation with syncope remained significant after multivariate adjustment [HR: 3.58 (1.32-9.71), P = 0.011]. Random survival forest (RSF) model provided significant improvement in prediction performance over Cox regression (precision: 0.80 vs. 0.69; recall: 0.79 vs. 0.68; AUC: 0.77 vs. 0.68; c-statistic: 0.79 vs. 0.67). Decision rules were generated by RSF model to predict VT/VF post-diagnosis. Conclusions: Effective risk stratification in congenital LQTS can be achieved by clinical history, electrocardiographic indices, and different investigation results, irrespective of underlying genetic defects. A machine learning approach using RSF can improve risk prediction over traditional Cox regression models.
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Affiliation(s)
- Gary Tse
- Tianjin Key Laboratory of Ionic-Molecular Function of Cardiovascular Disease, Department of Cardiology, Tianjin Institute of Cardiology, Second Hospital of Tianjin Medical University, Tianjin, China
- Faculty of Health and Medical Sciences, University of Surrey, Guildford, United Kingdom
| | - Sharen Lee
- Laboratory of Cardiovascular Physiology, Li Ka Shing Institute of Health Sciences, Hong Kong, China
| | - Jiandong Zhou
- School of Data Science, City University of Hong Kong, Hong Kong, China
| | - Tong Liu
- Faculty of Health and Medical Sciences, University of Surrey, Guildford, United Kingdom
| | - Ian Chi Kei Wong
- Centre for Safe Medication Practice and Research, Department of Pharmacology and Pharmacy, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong, China
- School of Pharmacy, University College London, London, United Kingdom
| | - Chloe Mak
- Department of Pathology, Hong Kong Children's Hospital, Hong Kong, China
| | - Ngai Shing Mok
- Department of Medicine and Geriatrics, Princess Margaret Hospital, Hong Kong, China
| | - Kamalan Jeevaratnam
- Faculty of Health and Medical Sciences, University of Surrey, Guildford, United Kingdom
| | - Qingpeng Zhang
- School of Data Science, City University of Hong Kong, Hong Kong, China
| | - Shuk Han Cheng
- Department of Biomedical Sciences, City University of Hong Kong, Hong Kong, China
| | - Wing Tak Wong
- State Key Laboratory of Agrobiotechnology, School of Life Sciences, Chinese University of Hong Kong, Hong Kong, China
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19
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Abstract
Long QT syndrome (LQTS) is a cardiovascular disorder characterized by an abnormality in cardiac repolarization leading to a prolonged QT interval and T-wave irregularities on the surface electrocardiogram. It is commonly associated with syncope, seizures, susceptibility to torsades de pointes, and risk for sudden death. LQTS is a rare genetic disorder and a major preventable cause of sudden cardiac death in the young. The availability of therapy for this lethal disease emphasizes the importance of early and accurate diagnosis. Additionally, understanding of the molecular mechanisms underlying LQTS could help to optimize genotype-specific treatments to prevent deaths in LQTS patients. In this review, we briefly summarize current knowledge regarding molecular underpinning of LQTS, in particular focusing on LQT1, LQT2, and LQT3, and discuss novel strategies to study ion channel dysfunction and drug-specific therapies in LQT1, LQT2, and LQT3 syndromes.
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Affiliation(s)
| | - Isabelle Deschênes
- Department of Physiology and Cell Biology, The Ohio State University, Columbus, Ohio
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20
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Streeten EA, See VY, Jeng LBJ, Maloney KA, Lynch M, Glazer AM, Yang T, Roden D, Pollin TI, Daue M, Ryan KA, Van Hout C, Gosalia N, Gonzaga-Jauregui C, Economides A, Perry JA, O'Connell J, Beitelshees A, Palmer K, Mitchell BD, Shuldiner AR. KCNQ1 and Long QT Syndrome in 1/45 Amish: The Road From Identification to Implementation of Culturally Appropriate Precision Medicine. CIRCULATION-GENOMIC AND PRECISION MEDICINE 2020; 13:e003133. [PMID: 33141630 PMCID: PMC7748050 DOI: 10.1161/circgen.120.003133] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Supplemental Digital Content is available in the text. In population-based research exome sequencing, the path from variant discovery to return of results is not well established. Variants discovered by research exome sequencing have the potential to improve population health.
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Affiliation(s)
- Elizabeth A Streeten
- Program for Personalized and Genomic Medicine (E.A.S., L.B.J.J., K.A.M., M.L., T.I.P., M.D., K.A.R., J.A.P., J.O., A.B., K.P., B.D.M.), University of Maryland School of Medicine.,Department of Medicine (E.A.S., V.Y.S., L.B.J.J., K.A.M., M.L., T.I.P., M.D., K.A.R., J.A.P., J.O., A.B., B.D.M.), University of Maryland School of Medicine
| | - Vincent Y See
- Department of Medicine (E.A.S., V.Y.S., L.B.J.J., K.A.M., M.L., T.I.P., M.D., K.A.R., J.A.P., J.O., A.B., B.D.M.), University of Maryland School of Medicine.,Division of Cardiolovascular Medicine (V.Y.S., T.I.P., K.P.), University of Maryland School of Medicine
| | - Linda B J Jeng
- Program for Personalized and Genomic Medicine (E.A.S., L.B.J.J., K.A.M., M.L., T.I.P., M.D., K.A.R., J.A.P., J.O., A.B., K.P., B.D.M.), University of Maryland School of Medicine.,Department of Medicine (E.A.S., V.Y.S., L.B.J.J., K.A.M., M.L., T.I.P., M.D., K.A.R., J.A.P., J.O., A.B., B.D.M.), University of Maryland School of Medicine
| | - Kristin A Maloney
- Program for Personalized and Genomic Medicine (E.A.S., L.B.J.J., K.A.M., M.L., T.I.P., M.D., K.A.R., J.A.P., J.O., A.B., K.P., B.D.M.), University of Maryland School of Medicine.,Department of Medicine (E.A.S., V.Y.S., L.B.J.J., K.A.M., M.L., T.I.P., M.D., K.A.R., J.A.P., J.O., A.B., B.D.M.), University of Maryland School of Medicine
| | - Megan Lynch
- Program for Personalized and Genomic Medicine (E.A.S., L.B.J.J., K.A.M., M.L., T.I.P., M.D., K.A.R., J.A.P., J.O., A.B., K.P., B.D.M.), University of Maryland School of Medicine.,Department of Medicine (E.A.S., V.Y.S., L.B.J.J., K.A.M., M.L., T.I.P., M.D., K.A.R., J.A.P., J.O., A.B., B.D.M.), University of Maryland School of Medicine
| | - Andrew M Glazer
- Division of Clinical Pharmacology, Department of Medicine (A.M.G., T.Y., D.R.), Vanderbilt University Medical Center, Nashville, TN
| | - Tao Yang
- Division of Clinical Pharmacology, Department of Medicine (A.M.G., T.Y., D.R.), Vanderbilt University Medical Center, Nashville, TN.,Department of Pharmacology (T.Y., D.R.), Vanderbilt University Medical Center, Nashville, TN
| | - Dan Roden
- Division of Clinical Pharmacology, Department of Medicine (A.M.G., T.Y., D.R.), Vanderbilt University Medical Center, Nashville, TN.,Department of Pharmacology (T.Y., D.R.), Vanderbilt University Medical Center, Nashville, TN.,Biomedical Informatics (D.R.), Vanderbilt University Medical Center, Nashville, TN
| | - Toni I Pollin
- Program for Personalized and Genomic Medicine (E.A.S., L.B.J.J., K.A.M., M.L., T.I.P., M.D., K.A.R., J.A.P., J.O., A.B., K.P., B.D.M.), University of Maryland School of Medicine.,Department of Medicine (E.A.S., V.Y.S., L.B.J.J., K.A.M., M.L., T.I.P., M.D., K.A.R., J.A.P., J.O., A.B., B.D.M.), University of Maryland School of Medicine.,Division of Cardiolovascular Medicine (V.Y.S., T.I.P., K.P.), University of Maryland School of Medicine
| | - Melanie Daue
- Program for Personalized and Genomic Medicine (E.A.S., L.B.J.J., K.A.M., M.L., T.I.P., M.D., K.A.R., J.A.P., J.O., A.B., K.P., B.D.M.), University of Maryland School of Medicine.,Department of Medicine (E.A.S., V.Y.S., L.B.J.J., K.A.M., M.L., T.I.P., M.D., K.A.R., J.A.P., J.O., A.B., B.D.M.), University of Maryland School of Medicine
| | - Kathleen A Ryan
- Program for Personalized and Genomic Medicine (E.A.S., L.B.J.J., K.A.M., M.L., T.I.P., M.D., K.A.R., J.A.P., J.O., A.B., K.P., B.D.M.), University of Maryland School of Medicine.,Department of Medicine (E.A.S., V.Y.S., L.B.J.J., K.A.M., M.L., T.I.P., M.D., K.A.R., J.A.P., J.O., A.B., B.D.M.), University of Maryland School of Medicine
| | - Cristopher Van Hout
- Regeneron Genetics Center LLC, Tarrytown, NY (C.V.H., N.G., C.G.-J., A.E., A.R.S.)
| | - Nehal Gosalia
- Regeneron Genetics Center LLC, Tarrytown, NY (C.V.H., N.G., C.G.-J., A.E., A.R.S.)
| | | | - Aris Economides
- Regeneron Genetics Center LLC, Tarrytown, NY (C.V.H., N.G., C.G.-J., A.E., A.R.S.)
| | - James A Perry
- Program for Personalized and Genomic Medicine (E.A.S., L.B.J.J., K.A.M., M.L., T.I.P., M.D., K.A.R., J.A.P., J.O., A.B., K.P., B.D.M.), University of Maryland School of Medicine.,Department of Medicine (E.A.S., V.Y.S., L.B.J.J., K.A.M., M.L., T.I.P., M.D., K.A.R., J.A.P., J.O., A.B., B.D.M.), University of Maryland School of Medicine
| | - Jeffrey O'Connell
- Program for Personalized and Genomic Medicine (E.A.S., L.B.J.J., K.A.M., M.L., T.I.P., M.D., K.A.R., J.A.P., J.O., A.B., K.P., B.D.M.), University of Maryland School of Medicine.,Department of Medicine (E.A.S., V.Y.S., L.B.J.J., K.A.M., M.L., T.I.P., M.D., K.A.R., J.A.P., J.O., A.B., B.D.M.), University of Maryland School of Medicine
| | - Amber Beitelshees
- Program for Personalized and Genomic Medicine (E.A.S., L.B.J.J., K.A.M., M.L., T.I.P., M.D., K.A.R., J.A.P., J.O., A.B., K.P., B.D.M.), University of Maryland School of Medicine.,Department of Medicine (E.A.S., V.Y.S., L.B.J.J., K.A.M., M.L., T.I.P., M.D., K.A.R., J.A.P., J.O., A.B., B.D.M.), University of Maryland School of Medicine
| | - Kathleen Palmer
- Program for Personalized and Genomic Medicine (E.A.S., L.B.J.J., K.A.M., M.L., T.I.P., M.D., K.A.R., J.A.P., J.O., A.B., K.P., B.D.M.), University of Maryland School of Medicine.,Division of Cardiolovascular Medicine (V.Y.S., T.I.P., K.P.), University of Maryland School of Medicine
| | - Braxton D Mitchell
- Program for Personalized and Genomic Medicine (E.A.S., L.B.J.J., K.A.M., M.L., T.I.P., M.D., K.A.R., J.A.P., J.O., A.B., K.P., B.D.M.), University of Maryland School of Medicine.,Department of Medicine (E.A.S., V.Y.S., L.B.J.J., K.A.M., M.L., T.I.P., M.D., K.A.R., J.A.P., J.O., A.B., B.D.M.), University of Maryland School of Medicine.,Baltimore Veterans Administration Medical Center Geriatrics Research and Education Clinical Center, Baltimore, MD (B.D.M.)
| | - Alan R Shuldiner
- Regeneron Genetics Center LLC, Tarrytown, NY (C.V.H., N.G., C.G.-J., A.E., A.R.S.)
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21
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Abstract
Cardiac arrhythmias are defined as electrical disorders of the pumping heart, including therein a wide range of physiopathological entities [...]
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22
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Kashiwa A, Aiba T, Makimoto H, Shimamoto K, Yamagata K, Kamakura T, Wada M, Miyamoto K, Inoue-Yamada Y, Ishibashi K, Noda T, Nagase S, Miyazaki A, Sakaguchi H, Shiraishi I, Yagihara N, Watanabe H, Aizawa Y, Makiyama T, Itoh H, Hayashi K, Yamagishi M, Sumitomo N, Yoshinaga M, Morita H, Ohe T, Miyamoto Y, Makita N, Yasuda S, Kusano K, Ohno S, Horie M, Shimizu W. Systematic Evaluation of KCNQ1 Variant Using ACMG/AMP Guidelines and Risk Stratification in Long QT Syndrome Type 1. CIRCULATION. GENOMIC AND PRECISION MEDICINE 2020. [PMID: 32936022 DOI: 10.1161/circgen.120.002926] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Background - Mutation/variant-site specific risk stratification in long-QT syndrome type 1 (LQT1) has been well investigated, but it is still challenging to adapt current enormous genomic information to clinical aspects caused by each mutation/variant. We assessed a novel variant-specific risk stratification in LQT1 patients. Methods - We classified a pathogenicity of 141 KCNQ1 variants among 927 LQT1 patients (536 probands) based on the American College of Medical Genetics and Genomics (ACMG) and Association for Molecular Pathology (AMP) guidelines and evaluated whether the ACMG/AMP-based classification was associated with arrhythmic risk in LQT1 patients. Results - Among 141 KCNQ1 variants, 61 (43.3%), 55 (39.0%), and 25 (17.7%) variants were classified into pathogenic (P), likely pathogenic (LP), and variant of unknown significance (VUS), respectively. Multivariable analysis showed that proband (HR = 2.53; 95%CI = 1.94-3.32; p <0.0001), longer QTc (≥500ms) (HR = 1.44; 95%CI = 1.13-1.83; p = 0.004), variants at membrane spanning (MS) (vs. those at N/C terminus) (HR = 1.42; 95%CI = 1.08-1.88; p = 0.01), C-loop (vs. N/C terminus) (HR = 1.52; 95%CI = 1.06-2.16; p = 0.02), and P variants [(vs. LP) (HR = 1.72; 95%CI = 1.32-2.26; p <0.0001), (vs. VUS) (HR = 1.81; 95%CI = 1.15-2.99; p = 0.009)] were significantly associated with syncopal events. The ACMG/AMP-based KCNQ1 evaluation was useful for risk stratification not only in family members but also in probands. A clinical score (0~4) based on proband, QTc (≥500ms), variant location (MS or C-loop) and P variant by ACMG/AMP guidelines allowed identification of patients more likely to have arrhythmic events. Conclusions - Comprehensive evaluation of clinical findings and pathogenicity of KCNQ1 variants based on the ACMG/AMP-based evaluation may stratify arrhythmic risk of congenital long-QT syndrome type 1.
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Affiliation(s)
- Asami Kashiwa
- Department of Cardiovascular Medicine, National Cerebral & Cardiovascular Center, Suita & Department of Cardiovascular & Medicine, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Takeshi Aiba
- Department of Cardiovascular Medicine, National Cerebral & Cardiovascular Center, Suita, Japan
| | - Hisaki Makimoto
- Department of Cardiovascular Medicine, National Cerebral & Cardiovascular Center, Suita, Japan
| | - Keiko Shimamoto
- Department of Cardiovascular Medicine, National Cerebral & Cardiovascular Center, Suita, Japan
| | - Kenichiro Yamagata
- Department of Cardiovascular Medicine, National Cerebral & Cardiovascular Center, Suita, Japan
| | - Tsukasa Kamakura
- Department of Cardiovascular Medicine, National Cerebral & Cardiovascular Center, Suita, Japan
| | - Mitsuru Wada
- Department of Cardiovascular Medicine, National Cerebral & Cardiovascular Center, Suita, Japan
| | - Koji Miyamoto
- Department of Cardiovascular Medicine, National Cerebral & Cardiovascular Center, Suita, Japan
| | - Yuko Inoue-Yamada
- Department of Cardiovascular Medicine, National Cerebral & Cardiovascular Center, Suita, Japan
| | - Kohei Ishibashi
- Department of Cardiovascular Medicine, National Cerebral & Cardiovascular Center, Suita, Japan
| | - Takashi Noda
- Department of Cardiovascular Medicine, National Cerebral & Cardiovascular Center, Suita, Japan
| | - Satoshi Nagase
- Department of Cardiovascular Medicine, National Cerebral & Cardiovascular Center, Suita, Japan
| | - Aya Miyazaki
- Department of Pediatric Cardiology, Shizuoka Children's Hospital, Shizuoka, Japan
| | - Heima Sakaguchi
- Department of Pediatric Cardiology, National Cerebral & Cardiovascular Center, Suita, Japan
| | - Isao Shiraishi
- Department of Pediatric Cardiology, National Cerebral & Cardiovascular Center, Suita, Japan
| | - Nobue Yagihara
- Department of Cardiovascular Biology & Medicine, Niigata University Graduate School of Medical & Dental Sciences, Niigata, Japan
| | - Hiroshi Watanabe
- Department of Cardiovascular Biology & Medicine, Niigata University Graduate School of Medical & Dental Sciences, Niigata, Japan
| | - Yoshifusa Aizawa
- Department of Cardiology, Tachikawa General Hospital, Niigata, Japan
| | - Takeru Makiyama
- Department of Cardiovascular & Medicine Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Hideki Itoh
- Division of Patient Safety, Hiroshima University Hospital, Hiroshima, Japan
| | - Kenshi Hayashi
- Department of Cardiovascular Medicine, Kanazawa University Graduate School of Medicine Science, Kanazawa, Japan
| | | | - Naotaka Sumitomo
- Department of Pediatric Cardiology, Saitama Medical University International Medical Center, Saitama, Japan
| | - Masao Yoshinaga
- Department of Pediatrics, Kagoshima Medical Center, Kagoshima, Japan
| | - Hiroshi Morita
- Department of Cardiovascular Therapeutics, Okayama University Graduate School of Medicine, Okayama, Japan
| | - Tohru Ohe
- Department of Cardiovascular Therapeutics, Okayama University Graduate School of Medicine, Okayama, Japan
| | - Yoshihiro Miyamoto
- Division of Preventive Cardiology, National Cerebral & Cardiovascular Center, Suita, Japan
| | - Naomasa Makita
- Omics Research Center, National Cerebral & Cardiovascular Center, Suita, Japan
| | - Satoshi Yasuda
- Department of Cardiovascular Medicine, National Cerebral & Cardiovascular Center, Suita, Japan
| | - Kengo Kusano
- Department of Cardiovascular Medicine, National Cerebral & Cardiovascular Center, Suita, Japan
| | - Seiko Ohno
- Department of Bioscience & Genetics, National Cerebral & Cardiovascular Center Suita, Japan
| | - Minoru Horie
- Department of Cardiovascular Medicine, Shiga University of Medical Science, Shiga, Japan
| | - Wataru Shimizu
- Department of Cardiovascular Medicine, Nippon Medical School, Tokyo, Japan
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23
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Gao Y, Han Z, Wu X, Lan R, Zhang X, Shen W, Liu Y, Liu X, Lan X, Xu B, Xu W. Next-generation sequencing identifies a novel heterozygous I229T mutation on LMNA associated with familial cardiac conduction disease. Medicine (Baltimore) 2020; 99:e21797. [PMID: 32846814 PMCID: PMC7447464 DOI: 10.1097/md.0000000000021797] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
LMNA gene encodes Lamin A and C (Lamin A/C), which are intermediate filament protein implicating in DNA replication and transcription. Mutations in LMNA are validated to cause cardiac conduction disease (CCD) and cardiomyopathy.In a Chinese family, we identified 5 members harboring the identical heterozygous LMNA (c.686T>C, I229T) disease-causing mutation, which was not found in the 535 healthy controls. In silico analysis, we revealed structural alteration in Lamin A/C I229T mutant. Furthermore, molecular docking identified human polycomb repressive complex 2 and Lamin A/C interact with higher affinity in the presence of I229T, thus may downregulate Nav1.5 channel expression.Our findings expanded the spectrum of mutations associated with CCD and were valuable in the genetic diagnosis and clinical screening for CCD. Molecular docking analysis provided useful information of increased binding affinity between mutant Lamin A/C and polycomb repressive complex 2. However, the concrete mechanism of LMNA mutation (I229T) remains undetermined in our study, future genetics and molecular studies are still needed.
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Affiliation(s)
- Yuan Gao
- Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School
- Nanjing Drum Tower Hospital Clinical College of Nanjing Medical University, Nanjing, Jiangsu Province, China
| | - Zhonglin Han
- Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School
| | - Xiang Wu
- Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School
| | - Rongfang Lan
- Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School
| | - Xinlin Zhang
- Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School
| | - Wenzhi Shen
- Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School
| | - Yu Liu
- Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School
| | - Xuehua Liu
- Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School
| | - Xi Lan
- Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School
| | - Biao Xu
- Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School
| | - Wei Xu
- Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School
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24
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Abstract
The main inherited cardiac arrhythmias are long QT syndrome, short QT syndrome, catecholaminergic polymorphic ventricular tachycardia and Brugada syndrome. These rare diseases are often the underlying cause of sudden cardiac death in young individuals and result from mutations in several genes encoding ion channels or proteins involved in their regulation. The genetic defects lead to alterations in the ionic currents that determine the morphology and duration of the cardiac action potential, and individuals with these disorders often present with syncope or a life-threatening arrhythmic episode. The diagnosis is based on clinical presentation and history, the characteristics of the electrocardiographic recording at rest and during exercise and genetic analyses. Management relies on pharmacological therapy, mostly β-adrenergic receptor blockers (specifically, propranolol and nadolol) and sodium and transient outward current blockers (such as quinidine), or surgical interventions, including left cardiac sympathetic denervation and implantation of a cardioverter-defibrillator. All these arrhythmias are potentially life-threatening and have substantial negative effects on the quality of life of patients. Future research should focus on the identification of genes associated with the diseases and other risk factors, improved risk stratification and, in particular for Brugada syndrome, effective therapies.
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25
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Tung M, Van Petegem F, Lauson S, Collier A, Hodgkinson K, Fernandez B, Connors S, Leather R, Sanatani S, Arbour L. Cardiac arrest in a mother and daughter and the identification of a novel
RYR2
variant, predisposing to low penetrant catecholaminergic polymorphic ventricular tachycardia in a four‐generation Canadian family. Mol Genet Genomic Med 2020; 8:e1151. [PMID: 31994352 PMCID: PMC7196448 DOI: 10.1002/mgg3.1151] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2019] [Accepted: 01/11/2020] [Indexed: 01/30/2023] Open
Abstract
Background Catecholaminergic polymorphic ventricular tachycardia (CPVT) is a rare inherited arrhythmia syndrome characterized by adrenergically driven ventricular arrhythmia predominantly caused by pathogenic variants in the cardiac ryanodine receptor (RyR2). We describe a novel variant associated with cardiac arrest in a mother and daughter. Methods Initial sequencing of the RYR2 gene identified a novel variant (c.527G > T, p.R176L) in the index case (the mother), and her daughter. Structural analysis demonstrated the variant was located within the N‐terminal domain of RyR2, likely leading to a gain‐of‐function effect facilitating enhanced calcium ion release. Four generation cascade genetic and clinical screening was carried out. Results Thirty‐eight p.R176L variant carriers were identified of 94 family members with genetic testing, and 108 family members had clinical evaluations. Twelve carriers were symptomatic with previous syncope and 2 additional survivors of cardiac arrest were identified. Thirty‐two had clinical features suggestive of CPVT. Of 52 noncarriers, 11 had experienced previous syncope with none exhibiting any clinical features of CPVT. A documented arrhythmic event rate of 2.89/1000 person‐years across all carriers was calculated. Conclusion The substantial variability in phenotype and the lower than previously reported penetrance is illustrative of the importance of exploring family variants beyond first‐degree relatives.
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Affiliation(s)
| | - Filip Van Petegem
- Department of Biochemistry and Molecular Biology University of British Columbia Vancouver BC Canada
| | - Samantha Lauson
- Division of Medical Genetics Island Health Victoria BC Canada
| | - Ashley Collier
- Provincial Medical Genetics Program Eastern Health St. John's NL Canada
| | - Kathy Hodgkinson
- Clinical Epidemiology and Genetics, Faculty of Medicine Memorial University of Newfoundland St John's NL Canada
| | - Bridget Fernandez
- Provincial Medical Genetics Program Eastern Health St. John's NL Canada
- Discipline of Genetics, Faculty of Medicine Memorial University of Newfoundland St John’s NL Canada
| | - Sean Connors
- Division of Cardiology Faculty of Medicine Memorial University of Newfoundland St John's NL Canada
| | | | - Shubhayan Sanatani
- Division of Cardiology Department of Pediatrics University of British Columbia Vancouver BC Canada
| | - Laura Arbour
- Division of Medical Genetics Island Health Victoria BC Canada
- Department of Medical Genetics University of British Columbia Vancouver BC Canada
- Division of Medical Sciences University of Victoria Victoria BC Canada
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26
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Jaouadi H, Bouyacoub Y, Chabrak S, Kraoua L, Zaroui A, Elouej S, Nagara M, Dallali H, Delague V, Levy N, Benkhalifa R, Mechmeche R, Zaffran S, Abdelhak S. Multiallelic rare variants support an oligogenic origin of sudden cardiac death in the young. Herz 2020; 46:94-102. [PMID: 31970460 DOI: 10.1007/s00059-019-04883-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2019] [Revised: 09/20/2019] [Accepted: 12/06/2019] [Indexed: 12/16/2022]
Abstract
Unexplained sudden death in the young is cardiovascular in most cases. Structural and conduction defects in cardiac-related genes can conspire to underlie sudden cardiac death. Here we report a clinical investigation and an extensive genetic assessment of a Tunisian family with sudden cardiac death in young members. In order to identify the family-genetic basis of sudden cardiac death, we performed Whole Exome Sequencing (WES), read depth copy-number-variation (CNV) screening and segregation analysis. We identify 6 ultra-rare pathogenic heterozygous variants in OBSCN, RYR2, DSC2, AKAP9, CACNA1C and RBM20 genes, and one homozygous splicing variant in TECRL gene consistent with an oligogenic model of inheritance. CNV analysis did not reveal any causative CNV consistent with the family phenotype. Overall, our results are highly suggestive for a cumulative effect of heterozygous missense variants as disease causation and to account for a greater disease severity among offspring. Our study further confirms the complexity of the inheritance of sudden cardiac death and highlights the utility of family-based WES and segregation analysis in the identification of family specific mutations within different cardiac genes pathways.
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Affiliation(s)
- Hager Jaouadi
- Biomedical Genomics and Oncogenetics Laboratory LR16IPT05, Institut Pasteur de Tunis, Université Tunis El Manar, 13 Place Pasteur, BP74-1002, Tunis, belvédère, Tunisia.
| | - Yosra Bouyacoub
- Biomedical Genomics and Oncogenetics Laboratory LR16IPT05, Institut Pasteur de Tunis, Université Tunis El Manar, 13 Place Pasteur, BP74-1002, Tunis, belvédère, Tunisia
| | - Sonia Chabrak
- Department of Cardiology, La Rabta Hospital, Tunis, Tunisia.,Faculty of Medicine of Tunis, Université Tunis El Manar, Tunis, Tunisia
| | - Lilia Kraoua
- Department of Congenital and Hereditary Diseases, Charles Nicolle Hospital, Tunis, Tunisia
| | - Amira Zaroui
- Faculty of Medicine of Tunis, Université Tunis El Manar, Tunis, Tunisia
| | - Sahar Elouej
- Aix Marseille University, INSERM, U1251, Marseille Medical Genetics, Marseille, France
| | - Majdi Nagara
- Biomedical Genomics and Oncogenetics Laboratory LR16IPT05, Institut Pasteur de Tunis, Université Tunis El Manar, 13 Place Pasteur, BP74-1002, Tunis, belvédère, Tunisia
| | - Hamza Dallali
- Biomedical Genomics and Oncogenetics Laboratory LR16IPT05, Institut Pasteur de Tunis, Université Tunis El Manar, 13 Place Pasteur, BP74-1002, Tunis, belvédère, Tunisia
| | - Valérie Delague
- Aix Marseille University, INSERM, U1251, Marseille Medical Genetics, Marseille, France
| | - Nicolas Levy
- Aix Marseille University, INSERM, U1251, Marseille Medical Genetics, Marseille, France
| | - Rym Benkhalifa
- Venoms and Therapeutic Biomolecules Laboratory LR16IPT08, Institut Pasteur de Tunis, Tunis, Tunisia
| | - Rachid Mechmeche
- Department of Cardiology, La Rabta Hospital, Tunis, Tunisia.,Faculty of Medicine of Tunis, Université Tunis El Manar, Tunis, Tunisia
| | - Stéphane Zaffran
- Aix Marseille University, INSERM, U1251, Marseille Medical Genetics, Marseille, France
| | - Sonia Abdelhak
- Biomedical Genomics and Oncogenetics Laboratory LR16IPT05, Institut Pasteur de Tunis, Université Tunis El Manar, 13 Place Pasteur, BP74-1002, Tunis, belvédère, Tunisia
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27
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Novel AKAP9 mutation and long QT syndrome in a patient with torsades des pointes. J Interv Card Electrophysiol 2019; 56:171-172. [PMID: 31418098 DOI: 10.1007/s10840-019-00606-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/22/2019] [Accepted: 08/02/2019] [Indexed: 10/26/2022]
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28
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Sala L, Gnecchi M, Schwartz PJ. Long QT Syndrome Modelling with Cardiomyocytes Derived from Human-induced Pluripotent Stem Cells. Arrhythm Electrophysiol Rev 2019; 8:105-110. [PMID: 31114684 PMCID: PMC6528025 DOI: 10.15420/aer.2019.1.1] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Long QT syndrome (LQTS) is a potentially severe arrhythmogenic disorder, associated with a prolonged QT interval and sudden death, caused by mutations in key genes regulating cardiac electrophysiology. Current strategies to study LQTS in vitro include heterologous systems or animal models. Despite their value, the overwhelming power of genetic tools has exposed the many limitations of these technologies. In 2010, human-induced pluripotent stem cells (hiPSCs) revolutionised the field and allowed scientists to study in vitro some of the disease traits of LQTS on hiPSC-derived cardiomyocytes (hiPSC-CMs) from LQTS patients. In this concise review we present how the hiPSC technology has been used to model three main forms of LQTS and the severe form of LQTS associated with mutations in calmodulin. We also introduce some of the most recent challenges that must be tackled in the upcoming years to successfully shift hiPSC-CMs from powerful in vitro disease modelling tools into assets to improve risk stratification and clinical decision-making.
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Affiliation(s)
- Luca Sala
- Istituto Auxologico Italiano, IRCCS, Laboratory of Cardiovascular Genetics Milan, Italy
| | - Massimiliano Gnecchi
- Coronary Care Unit and Laboratory of Experimental Cardiology for Cell and Molecular Therapy, IRCCS Policlinico San Matteo Foundation Pavia, Italy.,Department of Medicine, University of Cape Town Cape Town, South Africa
| | - Peter J Schwartz
- Istituto Auxologico Italiano, IRCCS, Laboratory of Cardiovascular Genetics Milan, Italy.,Istituto Auxologico Italiano, IRCCS, Center for Cardiac Arrhythmias of Genetic Origin Milan, Italy.,Cardiovascular Genetics Laboratory, Hatter Institute for Cardiovascular Research in Africa, Department of Medicine, University of Cape Town Cape Town, South Africa
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29
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Crotti L, Ghidoni A, Dagradi F. Genetics of Adult and Fetal Forms of Long QT Syndrome. GENETIC CAUSES OF CARDIAC DISEASE 2019. [DOI: 10.1007/978-3-030-27371-2_1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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30
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Schwartz PJ, Crotti L, George AL. Modifier genes for sudden cardiac death. Eur Heart J 2018; 39:3925-3931. [PMID: 30215713 PMCID: PMC6247660 DOI: 10.1093/eurheartj/ehy502] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/08/2018] [Accepted: 08/28/2018] [Indexed: 01/07/2023] Open
Abstract
Genetic conditions, even those associated with identical gene mutations, can present with variable clinical manifestations. One widely accepted explanation for this phenomenon is the existence of genetic factors capable of modifying the consequences of disease-causing mutations (modifier genes). Here, we address the concepts and principles by which genetic factors may be involved in modifying risk for cardiac arrhythmia, then discuss the current knowledge and interpretation of their contribution to clinical heterogeneity. We illustrate these concepts in the context of two important clinical conditions associated with risk for sudden cardiac death including a monogenic disorder (congenital long QT syndrome) in which the impact of modifier genes has been established, and a complex trait (life-threatening arrhythmias in acute myocardial infarction) for which the search for genetic modifiers of arrhythmic risk is more challenging. Advances in understanding the contribution of modifier genes to a higher or lower propensity towards sudden death should improve patient-specific risk stratification and be a major step towards precision medicine.
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Affiliation(s)
- Peter J Schwartz
- Istituto Auxologico Italiano, IRCCS, Center for Cardiac Arrhythmias of Genetic Origin and Laboratory of Cardiovascular Genetics, Via Pier Lombardo, 22, Milan, Italy
- Corresponding author. Tel: +39 02 55000408, Fax: +39 02 55000411, ;
| | - Lia Crotti
- Istituto Auxologico Italiano, IRCCS, Center for Cardiac Arrhythmias of Genetic Origin and Laboratory of Cardiovascular Genetics, Via Pier Lombardo, 22, Milan, Italy
- Department of Medicine and Surgery, University of Milano-Bicocca, Via Cadore, 48, Monza, Italy
- Istituto Auxologico Italiano, IRCCS, Department of Cardiovascular, Neural and Metabolic Sciences, San Luca Hospital, Piazzale Brescia 20, Milan, Italy
| | - Alfred L George
- Department of Pharmacology, Northwestern University Feinberg School of Medicine, Searle 8-510, East Superior Street, Chicago, IL, USA
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31
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A personalized, multiomics approach identifies genes involved in cardiac hypertrophy and heart failure. NPJ Syst Biol Appl 2018; 4:12. [PMID: 29507758 PMCID: PMC5825397 DOI: 10.1038/s41540-018-0046-3] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2017] [Revised: 12/14/2017] [Accepted: 01/12/2018] [Indexed: 11/08/2022] Open
Abstract
A traditional approach to investigate the genetic basis of complex diseases is to identify genes with a global change in expression between diseased and healthy individuals. However, population heterogeneity may undermine the effort to uncover genes with significant but individual contribution to the spectrum of disease phenotypes within a population. Here we investigate individual changes of gene expression when inducing hypertrophy and heart failure in 100 + strains of genetically distinct mice from the Hybrid Mouse Diversity Panel (HMDP). We find that genes whose expression fold-change correlates in a statistically significant way with the severity of the disease are either up or down-regulated across strains, and therefore missed by a traditional population-wide analysis of differential gene expression. Furthermore, those "fold-change" genes are enriched in human cardiac disease genes and form a dense co-regulated module strongly interacting with the cardiac hypertrophic signaling network in the human interactome. We validate our approach by showing that the knockdown of Hes1, predicted as a strong candidate, induces a dramatic reduction of hypertrophy by 80-90% in neonatal rat ventricular myocytes. Our results demonstrate that individualized approaches are crucial to identify genes underlying complex diseases as well as to develop personalized therapies.
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32
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Leroy J, Vandecasteele G, Fischmeister R. Cyclic AMP signaling in cardiac myocytes. CURRENT OPINION IN PHYSIOLOGY 2018. [DOI: 10.1016/j.cophys.2017.11.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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33
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Suryavanshi SV, Jadhav SM, McConnell BK. Polymorphisms/Mutations in A-Kinase Anchoring Proteins (AKAPs): Role in the Cardiovascular System. J Cardiovasc Dev Dis 2018; 5:E7. [PMID: 29370121 PMCID: PMC5872355 DOI: 10.3390/jcdd5010007] [Citation(s) in RCA: 18] [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: 01/05/2018] [Revised: 01/23/2018] [Accepted: 01/24/2018] [Indexed: 02/06/2023] Open
Abstract
A-kinase anchoring proteins (AKAPs) belong to a family of scaffolding proteins that bind to protein kinase A (PKA) by definition and a variety of crucial proteins, including kinases, phosphatases, and phosphodiesterases. By scaffolding these proteins together, AKAPs build a "signalosome" at specific subcellular locations and compartmentalize PKA signaling. Thus, AKAPs are important for signal transduction after upstream activation of receptors ensuring accuracy and precision of intracellular PKA-dependent signaling pathways. Since their discovery in the 1980s, AKAPs have been studied extensively in the heart and have been proven essential in mediating cyclic adenosine monophosphate (cAMP)-PKA signaling. Although expression of AKAPs in the heart is very low, cardiac-specific knock-outs of several AKAPs have a noteworthy cardiac phenotype. Moreover, single nucleotide polymorphisms and genetic mutations in crucial cardiac proteins play a substantial role in the pathophysiology of cardiovascular diseases (CVDs). Despite the significant role of AKAPs in the cardiovascular system, a limited amount of research has focused on the role of genetic polymorphisms and/or mutations in AKAPs in increasing the risk of CVDs. This review attempts to overview the available literature on the polymorphisms/mutations in AKAPs and their effects on human health with a special focus on CVDs.
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Affiliation(s)
- Santosh V Suryavanshi
- Department of Pharmacological and Pharmaceutical Sciences, University of Houston College of Pharmacy, Texas Medical Center, Houston, TX 77204, USA.
| | - Shweta M Jadhav
- Department of Pharmacological and Pharmaceutical Sciences, University of Houston College of Pharmacy, Texas Medical Center, Houston, TX 77204, USA.
| | - Bradley K McConnell
- Department of Pharmacological and Pharmaceutical Sciences, University of Houston College of Pharmacy, Texas Medical Center, Houston, TX 77204, USA.
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Exome analysis in 34 sudden unexplained death (SUD) victims mainly identified variants in channelopathy-associated genes. Int J Legal Med 2018; 132:1057-1065. [PMID: 29350269 DOI: 10.1007/s00414-018-1775-y] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2017] [Accepted: 01/09/2018] [Indexed: 12/12/2022]
Abstract
Sudden cardiac death (SCD) is one of the major causes of mortality worldwide, mostly involving coronary artery disease in the elderly. In contrary, sudden death events in young victims often represent the first manifestation of undetected genetic cardiac diseases, which remained without any symptoms during lifetime. Approximately 30% of these sudden death cases have no definite cardiac etiology after a comprehensive medicolegal investigation and are therefore termed as sudden unexplained death (SUD) cases. Advances in high-throughput sequencing approaches have provided an efficient diagnostic tool to identify likely pathogenic variants in cardiovascular disease-associated genes in otherwise autopsy-negative SUD cases. The aim of this study was to genetically investigate a cohort of 34 unexplained death cases by focusing on candidate genes associated with cardiomyopathies and channelopathies. Exome analysis identified potentially disease-causing sequence alterations in 29.4% of the 34 SUD cases. Six (17.6%) individuals had variants with likely functional effects in the channelopathy-associated genes AKAP9, KCNE5, RYR2, and SEMA3A. Interestingly, four of these six SUD individuals were younger than 18 years of age. Since the total SUD cohort of this study included five children and adolescents, post-mortem molecular autopsy screening indicates a high diagnostic yield within this age group. Molecular genetic testing represents a valuable approach to uncover the cause of death in some of the SUD victims; however, 70-80% of the cases still remain elusive, emphasizing the importance of additional research to better understand the pathological mechanisms leading to a sudden death event.
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Sala L, Bellin M, Mummery CL. Integrating cardiomyocytes from human pluripotent stem cells in safety pharmacology: has the time come? Br J Pharmacol 2017; 174:3749-3765. [PMID: 27641943 PMCID: PMC5647193 DOI: 10.1111/bph.13577] [Citation(s) in RCA: 91] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2016] [Revised: 07/27/2016] [Accepted: 08/11/2016] [Indexed: 12/20/2022] Open
Abstract
Cardiotoxicity is a severe side effect of drugs that induce structural or electrophysiological changes in heart muscle cells. As a result, the heart undergoes failure and potentially lethal arrhythmias. It is still a major reason for drug failure in preclinical and clinical phases of drug discovery. Current methods for predicting cardiotoxicity are based on guidelines that combine electrophysiological analysis of cell lines expressing ion channels ectopically in vitro with animal models and clinical trials. Although no new cases of drugs linked to lethal arrhythmias have been reported since the introduction of these guidelines in 2005, their limited predictive power likely means that potentially valuable drugs may not reach clinical practice. Human pluripotent stem cell-derived cardiomyocytes (hPSC-CMs) are now emerging as potentially more predictive alternatives, particularly for the early phases of preclinical research. However, these cells are phenotypically immature and culture and assay methods not standardized, which could be a hurdle to the development of predictive computational models and their implementation into the drug discovery pipeline, in contrast to the ambitions of the comprehensive pro-arrhythmia in vitro assay (CiPA) initiative. Here, we review present and future preclinical cardiotoxicity screening and suggest possible hPSC-CM-based strategies that may help to move the field forward. Coordinated efforts by basic scientists, companies and hPSC banks to standardize experimental conditions for generating reliable and reproducible safety indices will be helpful not only for cardiotoxicity prediction but also for precision medicine. LINKED ARTICLES This article is part of a themed section on New Insights into Cardiotoxicity Caused by Chemotherapeutic Agents. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v174.21/issuetoc.
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Affiliation(s)
- Luca Sala
- Department of Anatomy and EmbryologyLeiden University Medical CenterLeidenZAThe Netherlands
| | - Milena Bellin
- Department of Anatomy and EmbryologyLeiden University Medical CenterLeidenZAThe Netherlands
| | - Christine L Mummery
- Department of Anatomy and EmbryologyLeiden University Medical CenterLeidenZAThe Netherlands
- Department of Applied Stem Cell TechnologiesUniversity of TwenteEnschedeThe Netherlands
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36
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Crotti L, Lahtinen AM, Spazzolini C, Mastantuono E, Monti MC, Morassutto C, Parati G, Heradien M, Goosen A, Lichtner P, Meitinger T, Brink PA, Kontula K, Swan H, Schwartz PJ. Genetic Modifiers for the Long-QT Syndrome: How Important Is the Role of Variants in the 3' Untranslated Region of KCNQ1? ACTA ACUST UNITED AC 2017; 9:330-9. [PMID: 27531917 DOI: 10.1161/circgenetics.116.001419] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Accepted: 07/15/2016] [Indexed: 11/16/2022]
Abstract
BACKGROUND Long-QT syndrome is an inherited cardiac channelopathy characterized by delayed repolarization, risk of life-threatening arrhythmia, and significant clinical variability even within families. Three single-nucleotide polymorphisms (SNPs) in the 3' untranslated region of KCNQ1 were recently suggested to be associated with suppressed gene expression and hence decreased disease severity when located on the same haplotype with a disease-causing KCNQ1 mutation. We sought to replicate this finding in a larger and a genetically more homogeneous population of KCNQ1 mutation carriers. METHODS AND RESULTS The 3 SNPs (rs2519184, rs8234, and rs10798) were genotyped in a total of 747 KCNQ1 mutation carriers with A341V, G589D, or IVS7-2A>G mutation. The SNP haplotypes were assigned based on family trees. The SNP allele frequencies and clinical severity differed between the 3 mutation groups. The different SNP haplotypes were neither associated with heart rate-corrected QT interval duration (QTc) nor cardiac events in any of the 3 mutation groups. When the mutation groups were combined, the derived SNP haplotype of rs8234 and rs10798 located on the same haplotype with the mutation was associated with a shorter QTc interval (P<0.05) and a reduced occurrence of cardiac events (P<0.01), consistent with the previous finding. However, when the population-specific mutation was controlled for, both associations were no longer evident. CONCLUSIONS 3' Untranslated region SNPs are not acting as genetic modifiers in a large group of LQT1 patients. The confounding effect of merging a genetically and clinically heterogeneous group of patients needs to be taken into account when studying disease modifiers.
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Affiliation(s)
- Lia Crotti
- From the Center for Cardiac Arrhythmias of Genetic Origin and Laboratory of Cardiovascular Genetics, IRCCS Istituto Auxologico Italiano, Milan (L.C., C.S., P.J.S.); Department of Molecular Medicine (L.C.) and Department of Public Health (M.C.M., C.M.), Unit of Biostatistics and Clinical Epidemiology, University of Pavia, Pavia; Department of Cardiovascular, Neural and Metabolic Sciences, San Luca Hospital IRCCS Istituto Auxologico Italiano, Milan, Italy (L.C., G.P.); Department of Medicine, Helsinki University Central Hospital and University of Helsinki, Helsinki, Finland (A.M.L., K.K.); Institute of Human Genetics, Helmholtz Zentrum München, Neuherberg, Germany (E.M., P.L., T.M.); Department of Medicine and Surgery University of Milano-Bicocca, Milan, Italy (G.P.); Department of Internal Medicine, University of Stellenbosch, South Africa (M.H., A.G., P.A.B.); Institute of Human Genetics, Technische Universität München (T.M.); DZHK (German Centre for Cardiovascular Research), partner site Munich Heart Alliance, Munich, Germany (T.M.); and Heart and Lung Center, Helsinki University Central Hospital, Helsinki, Finland (H.S.).
| | - Annukka M Lahtinen
- From the Center for Cardiac Arrhythmias of Genetic Origin and Laboratory of Cardiovascular Genetics, IRCCS Istituto Auxologico Italiano, Milan (L.C., C.S., P.J.S.); Department of Molecular Medicine (L.C.) and Department of Public Health (M.C.M., C.M.), Unit of Biostatistics and Clinical Epidemiology, University of Pavia, Pavia; Department of Cardiovascular, Neural and Metabolic Sciences, San Luca Hospital IRCCS Istituto Auxologico Italiano, Milan, Italy (L.C., G.P.); Department of Medicine, Helsinki University Central Hospital and University of Helsinki, Helsinki, Finland (A.M.L., K.K.); Institute of Human Genetics, Helmholtz Zentrum München, Neuherberg, Germany (E.M., P.L., T.M.); Department of Medicine and Surgery University of Milano-Bicocca, Milan, Italy (G.P.); Department of Internal Medicine, University of Stellenbosch, South Africa (M.H., A.G., P.A.B.); Institute of Human Genetics, Technische Universität München (T.M.); DZHK (German Centre for Cardiovascular Research), partner site Munich Heart Alliance, Munich, Germany (T.M.); and Heart and Lung Center, Helsinki University Central Hospital, Helsinki, Finland (H.S.)
| | - Carla Spazzolini
- From the Center for Cardiac Arrhythmias of Genetic Origin and Laboratory of Cardiovascular Genetics, IRCCS Istituto Auxologico Italiano, Milan (L.C., C.S., P.J.S.); Department of Molecular Medicine (L.C.) and Department of Public Health (M.C.M., C.M.), Unit of Biostatistics and Clinical Epidemiology, University of Pavia, Pavia; Department of Cardiovascular, Neural and Metabolic Sciences, San Luca Hospital IRCCS Istituto Auxologico Italiano, Milan, Italy (L.C., G.P.); Department of Medicine, Helsinki University Central Hospital and University of Helsinki, Helsinki, Finland (A.M.L., K.K.); Institute of Human Genetics, Helmholtz Zentrum München, Neuherberg, Germany (E.M., P.L., T.M.); Department of Medicine and Surgery University of Milano-Bicocca, Milan, Italy (G.P.); Department of Internal Medicine, University of Stellenbosch, South Africa (M.H., A.G., P.A.B.); Institute of Human Genetics, Technische Universität München (T.M.); DZHK (German Centre for Cardiovascular Research), partner site Munich Heart Alliance, Munich, Germany (T.M.); and Heart and Lung Center, Helsinki University Central Hospital, Helsinki, Finland (H.S.)
| | - Elisa Mastantuono
- From the Center for Cardiac Arrhythmias of Genetic Origin and Laboratory of Cardiovascular Genetics, IRCCS Istituto Auxologico Italiano, Milan (L.C., C.S., P.J.S.); Department of Molecular Medicine (L.C.) and Department of Public Health (M.C.M., C.M.), Unit of Biostatistics and Clinical Epidemiology, University of Pavia, Pavia; Department of Cardiovascular, Neural and Metabolic Sciences, San Luca Hospital IRCCS Istituto Auxologico Italiano, Milan, Italy (L.C., G.P.); Department of Medicine, Helsinki University Central Hospital and University of Helsinki, Helsinki, Finland (A.M.L., K.K.); Institute of Human Genetics, Helmholtz Zentrum München, Neuherberg, Germany (E.M., P.L., T.M.); Department of Medicine and Surgery University of Milano-Bicocca, Milan, Italy (G.P.); Department of Internal Medicine, University of Stellenbosch, South Africa (M.H., A.G., P.A.B.); Institute of Human Genetics, Technische Universität München (T.M.); DZHK (German Centre for Cardiovascular Research), partner site Munich Heart Alliance, Munich, Germany (T.M.); and Heart and Lung Center, Helsinki University Central Hospital, Helsinki, Finland (H.S.)
| | - Maria Cristina Monti
- From the Center for Cardiac Arrhythmias of Genetic Origin and Laboratory of Cardiovascular Genetics, IRCCS Istituto Auxologico Italiano, Milan (L.C., C.S., P.J.S.); Department of Molecular Medicine (L.C.) and Department of Public Health (M.C.M., C.M.), Unit of Biostatistics and Clinical Epidemiology, University of Pavia, Pavia; Department of Cardiovascular, Neural and Metabolic Sciences, San Luca Hospital IRCCS Istituto Auxologico Italiano, Milan, Italy (L.C., G.P.); Department of Medicine, Helsinki University Central Hospital and University of Helsinki, Helsinki, Finland (A.M.L., K.K.); Institute of Human Genetics, Helmholtz Zentrum München, Neuherberg, Germany (E.M., P.L., T.M.); Department of Medicine and Surgery University of Milano-Bicocca, Milan, Italy (G.P.); Department of Internal Medicine, University of Stellenbosch, South Africa (M.H., A.G., P.A.B.); Institute of Human Genetics, Technische Universität München (T.M.); DZHK (German Centre for Cardiovascular Research), partner site Munich Heart Alliance, Munich, Germany (T.M.); and Heart and Lung Center, Helsinki University Central Hospital, Helsinki, Finland (H.S.)
| | - Caterina Morassutto
- From the Center for Cardiac Arrhythmias of Genetic Origin and Laboratory of Cardiovascular Genetics, IRCCS Istituto Auxologico Italiano, Milan (L.C., C.S., P.J.S.); Department of Molecular Medicine (L.C.) and Department of Public Health (M.C.M., C.M.), Unit of Biostatistics and Clinical Epidemiology, University of Pavia, Pavia; Department of Cardiovascular, Neural and Metabolic Sciences, San Luca Hospital IRCCS Istituto Auxologico Italiano, Milan, Italy (L.C., G.P.); Department of Medicine, Helsinki University Central Hospital and University of Helsinki, Helsinki, Finland (A.M.L., K.K.); Institute of Human Genetics, Helmholtz Zentrum München, Neuherberg, Germany (E.M., P.L., T.M.); Department of Medicine and Surgery University of Milano-Bicocca, Milan, Italy (G.P.); Department of Internal Medicine, University of Stellenbosch, South Africa (M.H., A.G., P.A.B.); Institute of Human Genetics, Technische Universität München (T.M.); DZHK (German Centre for Cardiovascular Research), partner site Munich Heart Alliance, Munich, Germany (T.M.); and Heart and Lung Center, Helsinki University Central Hospital, Helsinki, Finland (H.S.)
| | - Gianfranco Parati
- From the Center for Cardiac Arrhythmias of Genetic Origin and Laboratory of Cardiovascular Genetics, IRCCS Istituto Auxologico Italiano, Milan (L.C., C.S., P.J.S.); Department of Molecular Medicine (L.C.) and Department of Public Health (M.C.M., C.M.), Unit of Biostatistics and Clinical Epidemiology, University of Pavia, Pavia; Department of Cardiovascular, Neural and Metabolic Sciences, San Luca Hospital IRCCS Istituto Auxologico Italiano, Milan, Italy (L.C., G.P.); Department of Medicine, Helsinki University Central Hospital and University of Helsinki, Helsinki, Finland (A.M.L., K.K.); Institute of Human Genetics, Helmholtz Zentrum München, Neuherberg, Germany (E.M., P.L., T.M.); Department of Medicine and Surgery University of Milano-Bicocca, Milan, Italy (G.P.); Department of Internal Medicine, University of Stellenbosch, South Africa (M.H., A.G., P.A.B.); Institute of Human Genetics, Technische Universität München (T.M.); DZHK (German Centre for Cardiovascular Research), partner site Munich Heart Alliance, Munich, Germany (T.M.); and Heart and Lung Center, Helsinki University Central Hospital, Helsinki, Finland (H.S.)
| | - Marshall Heradien
- From the Center for Cardiac Arrhythmias of Genetic Origin and Laboratory of Cardiovascular Genetics, IRCCS Istituto Auxologico Italiano, Milan (L.C., C.S., P.J.S.); Department of Molecular Medicine (L.C.) and Department of Public Health (M.C.M., C.M.), Unit of Biostatistics and Clinical Epidemiology, University of Pavia, Pavia; Department of Cardiovascular, Neural and Metabolic Sciences, San Luca Hospital IRCCS Istituto Auxologico Italiano, Milan, Italy (L.C., G.P.); Department of Medicine, Helsinki University Central Hospital and University of Helsinki, Helsinki, Finland (A.M.L., K.K.); Institute of Human Genetics, Helmholtz Zentrum München, Neuherberg, Germany (E.M., P.L., T.M.); Department of Medicine and Surgery University of Milano-Bicocca, Milan, Italy (G.P.); Department of Internal Medicine, University of Stellenbosch, South Africa (M.H., A.G., P.A.B.); Institute of Human Genetics, Technische Universität München (T.M.); DZHK (German Centre for Cardiovascular Research), partner site Munich Heart Alliance, Munich, Germany (T.M.); and Heart and Lung Center, Helsinki University Central Hospital, Helsinki, Finland (H.S.)
| | - Althea Goosen
- From the Center for Cardiac Arrhythmias of Genetic Origin and Laboratory of Cardiovascular Genetics, IRCCS Istituto Auxologico Italiano, Milan (L.C., C.S., P.J.S.); Department of Molecular Medicine (L.C.) and Department of Public Health (M.C.M., C.M.), Unit of Biostatistics and Clinical Epidemiology, University of Pavia, Pavia; Department of Cardiovascular, Neural and Metabolic Sciences, San Luca Hospital IRCCS Istituto Auxologico Italiano, Milan, Italy (L.C., G.P.); Department of Medicine, Helsinki University Central Hospital and University of Helsinki, Helsinki, Finland (A.M.L., K.K.); Institute of Human Genetics, Helmholtz Zentrum München, Neuherberg, Germany (E.M., P.L., T.M.); Department of Medicine and Surgery University of Milano-Bicocca, Milan, Italy (G.P.); Department of Internal Medicine, University of Stellenbosch, South Africa (M.H., A.G., P.A.B.); Institute of Human Genetics, Technische Universität München (T.M.); DZHK (German Centre for Cardiovascular Research), partner site Munich Heart Alliance, Munich, Germany (T.M.); and Heart and Lung Center, Helsinki University Central Hospital, Helsinki, Finland (H.S.)
| | - Peter Lichtner
- From the Center for Cardiac Arrhythmias of Genetic Origin and Laboratory of Cardiovascular Genetics, IRCCS Istituto Auxologico Italiano, Milan (L.C., C.S., P.J.S.); Department of Molecular Medicine (L.C.) and Department of Public Health (M.C.M., C.M.), Unit of Biostatistics and Clinical Epidemiology, University of Pavia, Pavia; Department of Cardiovascular, Neural and Metabolic Sciences, San Luca Hospital IRCCS Istituto Auxologico Italiano, Milan, Italy (L.C., G.P.); Department of Medicine, Helsinki University Central Hospital and University of Helsinki, Helsinki, Finland (A.M.L., K.K.); Institute of Human Genetics, Helmholtz Zentrum München, Neuherberg, Germany (E.M., P.L., T.M.); Department of Medicine and Surgery University of Milano-Bicocca, Milan, Italy (G.P.); Department of Internal Medicine, University of Stellenbosch, South Africa (M.H., A.G., P.A.B.); Institute of Human Genetics, Technische Universität München (T.M.); DZHK (German Centre for Cardiovascular Research), partner site Munich Heart Alliance, Munich, Germany (T.M.); and Heart and Lung Center, Helsinki University Central Hospital, Helsinki, Finland (H.S.)
| | - Thomas Meitinger
- From the Center for Cardiac Arrhythmias of Genetic Origin and Laboratory of Cardiovascular Genetics, IRCCS Istituto Auxologico Italiano, Milan (L.C., C.S., P.J.S.); Department of Molecular Medicine (L.C.) and Department of Public Health (M.C.M., C.M.), Unit of Biostatistics and Clinical Epidemiology, University of Pavia, Pavia; Department of Cardiovascular, Neural and Metabolic Sciences, San Luca Hospital IRCCS Istituto Auxologico Italiano, Milan, Italy (L.C., G.P.); Department of Medicine, Helsinki University Central Hospital and University of Helsinki, Helsinki, Finland (A.M.L., K.K.); Institute of Human Genetics, Helmholtz Zentrum München, Neuherberg, Germany (E.M., P.L., T.M.); Department of Medicine and Surgery University of Milano-Bicocca, Milan, Italy (G.P.); Department of Internal Medicine, University of Stellenbosch, South Africa (M.H., A.G., P.A.B.); Institute of Human Genetics, Technische Universität München (T.M.); DZHK (German Centre for Cardiovascular Research), partner site Munich Heart Alliance, Munich, Germany (T.M.); and Heart and Lung Center, Helsinki University Central Hospital, Helsinki, Finland (H.S.)
| | - Paul A Brink
- From the Center for Cardiac Arrhythmias of Genetic Origin and Laboratory of Cardiovascular Genetics, IRCCS Istituto Auxologico Italiano, Milan (L.C., C.S., P.J.S.); Department of Molecular Medicine (L.C.) and Department of Public Health (M.C.M., C.M.), Unit of Biostatistics and Clinical Epidemiology, University of Pavia, Pavia; Department of Cardiovascular, Neural and Metabolic Sciences, San Luca Hospital IRCCS Istituto Auxologico Italiano, Milan, Italy (L.C., G.P.); Department of Medicine, Helsinki University Central Hospital and University of Helsinki, Helsinki, Finland (A.M.L., K.K.); Institute of Human Genetics, Helmholtz Zentrum München, Neuherberg, Germany (E.M., P.L., T.M.); Department of Medicine and Surgery University of Milano-Bicocca, Milan, Italy (G.P.); Department of Internal Medicine, University of Stellenbosch, South Africa (M.H., A.G., P.A.B.); Institute of Human Genetics, Technische Universität München (T.M.); DZHK (German Centre for Cardiovascular Research), partner site Munich Heart Alliance, Munich, Germany (T.M.); and Heart and Lung Center, Helsinki University Central Hospital, Helsinki, Finland (H.S.)
| | - Kimmo Kontula
- From the Center for Cardiac Arrhythmias of Genetic Origin and Laboratory of Cardiovascular Genetics, IRCCS Istituto Auxologico Italiano, Milan (L.C., C.S., P.J.S.); Department of Molecular Medicine (L.C.) and Department of Public Health (M.C.M., C.M.), Unit of Biostatistics and Clinical Epidemiology, University of Pavia, Pavia; Department of Cardiovascular, Neural and Metabolic Sciences, San Luca Hospital IRCCS Istituto Auxologico Italiano, Milan, Italy (L.C., G.P.); Department of Medicine, Helsinki University Central Hospital and University of Helsinki, Helsinki, Finland (A.M.L., K.K.); Institute of Human Genetics, Helmholtz Zentrum München, Neuherberg, Germany (E.M., P.L., T.M.); Department of Medicine and Surgery University of Milano-Bicocca, Milan, Italy (G.P.); Department of Internal Medicine, University of Stellenbosch, South Africa (M.H., A.G., P.A.B.); Institute of Human Genetics, Technische Universität München (T.M.); DZHK (German Centre for Cardiovascular Research), partner site Munich Heart Alliance, Munich, Germany (T.M.); and Heart and Lung Center, Helsinki University Central Hospital, Helsinki, Finland (H.S.)
| | - Heikki Swan
- From the Center for Cardiac Arrhythmias of Genetic Origin and Laboratory of Cardiovascular Genetics, IRCCS Istituto Auxologico Italiano, Milan (L.C., C.S., P.J.S.); Department of Molecular Medicine (L.C.) and Department of Public Health (M.C.M., C.M.), Unit of Biostatistics and Clinical Epidemiology, University of Pavia, Pavia; Department of Cardiovascular, Neural and Metabolic Sciences, San Luca Hospital IRCCS Istituto Auxologico Italiano, Milan, Italy (L.C., G.P.); Department of Medicine, Helsinki University Central Hospital and University of Helsinki, Helsinki, Finland (A.M.L., K.K.); Institute of Human Genetics, Helmholtz Zentrum München, Neuherberg, Germany (E.M., P.L., T.M.); Department of Medicine and Surgery University of Milano-Bicocca, Milan, Italy (G.P.); Department of Internal Medicine, University of Stellenbosch, South Africa (M.H., A.G., P.A.B.); Institute of Human Genetics, Technische Universität München (T.M.); DZHK (German Centre for Cardiovascular Research), partner site Munich Heart Alliance, Munich, Germany (T.M.); and Heart and Lung Center, Helsinki University Central Hospital, Helsinki, Finland (H.S.)
| | - Peter J Schwartz
- From the Center for Cardiac Arrhythmias of Genetic Origin and Laboratory of Cardiovascular Genetics, IRCCS Istituto Auxologico Italiano, Milan (L.C., C.S., P.J.S.); Department of Molecular Medicine (L.C.) and Department of Public Health (M.C.M., C.M.), Unit of Biostatistics and Clinical Epidemiology, University of Pavia, Pavia; Department of Cardiovascular, Neural and Metabolic Sciences, San Luca Hospital IRCCS Istituto Auxologico Italiano, Milan, Italy (L.C., G.P.); Department of Medicine, Helsinki University Central Hospital and University of Helsinki, Helsinki, Finland (A.M.L., K.K.); Institute of Human Genetics, Helmholtz Zentrum München, Neuherberg, Germany (E.M., P.L., T.M.); Department of Medicine and Surgery University of Milano-Bicocca, Milan, Italy (G.P.); Department of Internal Medicine, University of Stellenbosch, South Africa (M.H., A.G., P.A.B.); Institute of Human Genetics, Technische Universität München (T.M.); DZHK (German Centre for Cardiovascular Research), partner site Munich Heart Alliance, Munich, Germany (T.M.); and Heart and Lung Center, Helsinki University Central Hospital, Helsinki, Finland (H.S.)
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Forleo C, D’Erchia AM, Sorrentino S, Manzari C, Chiara M, Iacoviello M, Guaricci AI, De Santis D, Musci RL, La Spada A, Marangelli V, Pesole G, Favale S. Targeted next-generation sequencing detects novel gene-phenotype associations and expands the mutational spectrum in cardiomyopathies. PLoS One 2017; 12:e0181842. [PMID: 28750076 PMCID: PMC5531468 DOI: 10.1371/journal.pone.0181842] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2017] [Accepted: 07/08/2017] [Indexed: 12/19/2022] Open
Abstract
Cardiomyopathies are a heterogeneous group of primary diseases of the myocardium, including hypertrophic cardiomyopathy (HCM), dilated cardiomyopathy (DCM), and arrhythmogenic right ventricular cardiomyopathy (ARVC), with higher morbidity and mortality. These diseases are genetically diverse and associated with rare mutations in a large number of genes, many of which overlap among the phenotypes. To better investigate the genetic overlap between these three phenotypes and to identify new genotype–phenotype correlations, we designed a custom gene panel consisting of 115 genes known to be associated with cardiomyopathic phenotypes and channelopathies. A cohort of 38 unrelated patients, 16 affected by DCM, 14 by HCM and 8 by ARVC, was recruited for the study on the basis of more severe phenotypes and family history of cardiomyopathy and/or sudden death. We detected a total of 142 rare variants in 40 genes, and all patients were found to be carriers of at least one rare variant. Twenty-eight of the 142 rare variants were also predicted as potentially pathogenic variants and found in 26 patients. In 23 out of 38 patients, we found at least one novel potential gene–phenotype association. In particular, we detected three variants in OBSCN gene in ARVC patients, four variants in ANK2 gene and two variants in DLG1, TRPM4, and AKAP9 genes in DCM patients, two variants in PSEN2 gene and four variants in AKAP9 gene in HCM patients. Overall, our results confirmed that cardiomyopathic patients could carry multiple rare gene variants; in addition, our investigation of the genetic overlap among cardiomyopathies revealed new gene–phenotype associations. Furthermore, as our study confirms, data obtained using targeted next-generation sequencing could provide a remarkable contribution to the molecular diagnosis of cardiomyopathies, early identification of patients at risk for arrhythmia development, and better clinical management of cardiomyopathic patients.
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Affiliation(s)
- Cinzia Forleo
- Cardiology Unit, Department of Emergency and Organ Transplantation, University of Bari Aldo Moro, Bari, Italy
- * E-mail: (CF); (AMD)
| | - Anna Maria D’Erchia
- Department of Biosciences, Biotechnology and Biopharmaceutics, University of Bari Aldo Moro, Bari, Italy
- Institute of Biomembranes, Bioenergetics and Molecular Biotechnologies (IBIOM), National Research Council, Bari, Italy
- * E-mail: (CF); (AMD)
| | - Sandro Sorrentino
- Cardiology Unit, Department of Emergency and Organ Transplantation, University of Bari Aldo Moro, Bari, Italy
| | - Caterina Manzari
- Institute of Biomembranes, Bioenergetics and Molecular Biotechnologies (IBIOM), National Research Council, Bari, Italy
| | - Matteo Chiara
- Department of Biosciences, University of Milano, Milano, Italy
| | - Massimo Iacoviello
- Cardiology Unit, Department of Emergency and Organ Transplantation, University of Bari Aldo Moro, Bari, Italy
| | - Andrea Igoren Guaricci
- Cardiology Unit, Department of Emergency and Organ Transplantation, University of Bari Aldo Moro, Bari, Italy
| | - Delia De Santis
- Cardiology Unit, Department of Emergency and Organ Transplantation, University of Bari Aldo Moro, Bari, Italy
| | - Rita Leonarda Musci
- Cardiology Unit, Department of Emergency and Organ Transplantation, University of Bari Aldo Moro, Bari, Italy
| | - Antonino La Spada
- Cardiology Unit, Department of Emergency and Organ Transplantation, University of Bari Aldo Moro, Bari, Italy
| | - Vito Marangelli
- Cardiology Unit, Department of Emergency and Organ Transplantation, University of Bari Aldo Moro, Bari, Italy
| | - Graziano Pesole
- Department of Biosciences, Biotechnology and Biopharmaceutics, University of Bari Aldo Moro, Bari, Italy
- Institute of Biomembranes, Bioenergetics and Molecular Biotechnologies (IBIOM), National Research Council, Bari, Italy
| | - Stefano Favale
- Cardiology Unit, Department of Emergency and Organ Transplantation, University of Bari Aldo Moro, Bari, Italy
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Harmer SC, Tinker A. The impact of recent advances in genetics in understanding disease mechanisms underlying the long QT syndromes. Biol Chem 2017; 397:679-93. [PMID: 26910742 DOI: 10.1515/hsz-2015-0306] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2015] [Accepted: 02/18/2016] [Indexed: 11/15/2022]
Abstract
Long QT syndrome refers to a characteristic abnormality of the electrocardiogram and it is associated with a form of ventricular tachycardia known as torsade-de-pointes and sudden arrhythmic death. It can occur as part of a hereditary syndrome or can be acquired usually because of drug administration. Here we review recent genetic, molecular and cellular discoveries and outline how they have furthered our understanding of this disease. Specifically we focus on compound mutations, genome wide association studies of QT interval, modifier genes and the therapeutic implications of this recent work.
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Hof T, Liu H, Sallé L, Schott JJ, Ducreux C, Millat G, Chevalier P, Probst V, Guinamard R, Bouvagnet P. TRPM4 non-selective cation channel variants in long QT syndrome. BMC MEDICAL GENETICS 2017; 18:31. [PMID: 28315637 PMCID: PMC5357330 DOI: 10.1186/s12881-017-0397-4] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/25/2016] [Accepted: 03/08/2017] [Indexed: 12/21/2022]
Abstract
Background Long QT syndrome (LQTS) is an inherited arrhythmic disorder characterized by prolongation of the QT interval, a risk of syncope, and sudden death. There are already a number of causal genes in LQTS, but not all LQTS patients have an identified mutation, which suggests LQTS unknown genes. Methods A cohort of 178 LQTS patients, with no mutations in the 3 major LQTS genes (KCNQ1, KCNH2, and SCN5A), was screened for mutations in the transient potential melastatin 4 gene (TRPM4). Results Four TRPM4 variants (2.2% of the cohort) were found to change highly conserved amino-acids and were either very rare or absent from control populations. Therefore, these four TRPM4 variants were predicted to be disease causing. Furthermore, no mutations were found in the DNA of these TRPM4 variant carriers in any of the 13 major long QT syndrome genes. Two of these variants were further studied by electrophysiology (p.Val441Met and p.Arg499Pro). Both variants showed a classical TRPM4 outward rectifying current, but the current was reduced by 61 and 90% respectively, compared to wild type TRPM4 current. Conclusions This study supports the view that TRPM4 could account for a small percentage of LQTS patients. TRPM4 contribution to the QT interval might be multifactorial by modulating whole cell current but also, as shown in Trpm4−/− mice, by modulating cardiomyocyte proliferation. TRPM4 enlarges the subgroup of LQT genes (KCNJ2 in Andersen syndrome and CACNA1C in Timothy syndrome) known to increase the QT interval through a more complex pleiotropic effect than merely action potential alteration.
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Affiliation(s)
- Thomas Hof
- Normandie University, UNICAEN, EA 4650, Groupe Signalisation, Electrophysiologie et Imagerie des Lésions d'Ischémie-Reperfusion Myocardique, F-14032, Caen, France
| | - Hui Liu
- Laboratoire Cardiogénétique, Institut de Biologie et Chimie des Protéines, INSERM UMR 5305, Université Lyon 1, Lyon, France.,Laboratoire Cardiogénétique, Centre de Biologie et Pathologie Est, Hospices Civils de Lyon, Bron, France.,Present Address: Department of Anatomy, Hainan Medical College, Haikou, 571101, Hainan, China
| | - Laurent Sallé
- Normandie University, UNICAEN, EA 4650, Groupe Signalisation, Electrophysiologie et Imagerie des Lésions d'Ischémie-Reperfusion Myocardique, F-14032, Caen, France
| | | | - Corinne Ducreux
- Service de Cardiologie Pédiatrique, Hôpital Louis Pradel, Bron, France
| | - Gilles Millat
- Laboratoire Cardiogénétique Moléculaire, Centre de Biologie et Pathologie Est, Hospices Civils de Lyon, Bron, France
| | | | - Vincent Probst
- Institut du thorax, INSERM UMR 1087, CNRS UMR 6291, Nantes, France.,Institut du thorax, Service de Cardiologie, CHU Nantes, Nantes, France
| | - Romain Guinamard
- Normandie University, UNICAEN, EA 4650, Groupe Signalisation, Electrophysiologie et Imagerie des Lésions d'Ischémie-Reperfusion Myocardique, F-14032, Caen, France
| | - Patrice Bouvagnet
- Laboratoire Cardiogénétique, Institut de Biologie et Chimie des Protéines, INSERM UMR 5305, Université Lyon 1, Lyon, France. .,Laboratoire Cardiogénétique, Centre de Biologie et Pathologie Est, Hospices Civils de Lyon, Bron, France. .,Service de Cardiologie Pédiatrique, Hôpital Louis Pradel, Bron, France. .,Laboratoire Cardiogénétique, Groupe Hospitalier Est, 59 boulevard Pinel, CBPE, 69677, Bron, France.
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Kapplinger JD, Erickson A, Asuri S, Tester DJ, McIntosh S, Kerr CR, Morrison J, Tang A, Sanatani S, Arbour L, Ackerman MJ. KCNQ1 p.L353L affects splicing and modifies the phenotype in a founder population with long QT syndrome type 1. J Med Genet 2017; 54:390-398. [PMID: 28264985 PMCID: PMC5502312 DOI: 10.1136/jmedgenet-2016-104153] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2016] [Revised: 11/30/2016] [Accepted: 12/19/2016] [Indexed: 12/23/2022]
Abstract
Background Variable expressivity and incomplete penetrance between individuals with identical long QT syndrome (LQTS) causative mutations largely remain unexplained. Founder populations provide a unique opportunity to explore modifying genetic effects. We examined the role of a novel synonymous KCNQ1 p.L353L variant on the splicing of exon 8 and on heart rate corrected QT interval (QTc) in a population known to have a pathogenic LQTS type 1 (LQTS1) causative mutation, p.V205M, in KCNQ1-encoded Kv7.1. Methods 419 adults were genotyped for p.V205M, p.L353L and a previously described QTc modifier (KCNH2-p.K897T). Adjusted linear regression determined the effect of each variant on QTc, alone and in combination. In addition, peripheral blood RNA was extracted from three controls and three p.L353L-positive individuals. The mutant transcript levels were assessed via qPCR and normalised to overall KCNQ1 transcript levels to assess the effect on splicing. Results For women and men, respectively, p.L353L alone conferred a 10.0 (p=0.064) ms and 14.0 (p=0.014) ms increase in QTc and in men only a significant interaction effect in combination with the p.V205M (34.6 ms, p=0.003) resulting in a QTc of ∼500 ms. The mechanism of p.L353L's effect was attributed to approximately threefold increase in exon 8 exclusion resulting in ∼25% mutant transcripts of the total KCNQ1 transcript levels. Conclusions Our results provide the first evidence that synonymous variants outside the canonical splice sites in KCNQ1 can alter splicing and clinically impact phenotype. Through this mechanism, we identified that p.L353L can precipitate QT prolongation by itself and produce a clinically relevant interactive effect in conjunction with other LQTS variants.
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Affiliation(s)
- Jamie D Kapplinger
- Mayo Medical School, Mayo Clinic, Rochester, Minnesota, USA.,Department of Molecular Pharmacology & Experimental Therapeutics, Windland Smith Rice Sudden Death Genomics Laboratory, Mayo Clinic, Rochester, Minnesota, USA
| | - Anders Erickson
- Division of Medical Sciences, University of Victoria, Victoria, British Columbia, Canada
| | - Sirisha Asuri
- Department of Medical Genetics, University of British Columbia, Vancouver, British Columbia, Canada
| | - David J Tester
- Division of Heart Rhythm Services, Department of Cardiovascular Diseases, Mayo Clinic, Rochester, Minnesota, USA
| | - Sarah McIntosh
- Department of Medical Genetics, University of British Columbia, Vancouver, British Columbia, Canada
| | - Charles R Kerr
- Division of Cardiology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Julie Morrison
- Gitxsan Health Society, Hazelton, British Columbia, Canada
| | - Anthony Tang
- Department of Medicine, University of Western Ontario, London, Ontario, Canada
| | - Shubhayan Sanatani
- Division of Cardiology, Department of Pediatrics, University of British Columbia, BC Children's Hospital, Vancouver, British Columbia, Canada
| | - Laura Arbour
- Division of Medical Sciences, University of Victoria, Victoria, British Columbia, Canada.,Department of Medical Genetics, University of British Columbia, Vancouver, British Columbia, Canada
| | - Michael J Ackerman
- Mayo Medical School, Mayo Clinic, Rochester, Minnesota, USA.,Department of Molecular Pharmacology & Experimental Therapeutics, Windland Smith Rice Sudden Death Genomics Laboratory, Mayo Clinic, Rochester, Minnesota, USA.,Division of Heart Rhythm Services, Department of Cardiovascular Diseases, Mayo Clinic, Rochester, Minnesota, USA.,Division of Pediatric Cardiology, Department of Pediatrics, Mayo Clinic, Rochester, Minnesota, USA
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Abstract
Approximately 80 genes in the human genome code for pore-forming subunits of potassium (K(+)) channels. Rare variants (mutations) in K(+) channel-encoding genes may cause heritable arrhythmia syndromes. Not all rare variants in K(+) channel-encoding genes are necessarily disease-causing mutations. Common variants in K(+) channel-encoding genes are increasingly recognized as modifiers of phenotype in heritable arrhythmia syndromes and in the general population. Although difficult, distinguishing pathogenic variants from benign variants is of utmost importance to avoid false designations of genetic variants as disease-causing mutations.
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Affiliation(s)
- Ahmad S Amin
- Department of Clinical and Experimental Cardiology, Heart Centre, Academic Medical Center, University of Amsterdam, Meibergdreef 9, Amsterdam 1105 AZ, The Netherlands
| | - Arthur A M Wilde
- Department of Clinical and Experimental Cardiology, Heart Centre, Academic Medical Center, University of Amsterdam, Meibergdreef 9, Amsterdam 1105 AZ, The Netherlands; King Abdulaziz University, Princess Al-Jawhara Al-Brahim Centre of Excellence in Research of Hereditary Disorders, PO Box 80200, Jeddah 21589, Kingdom of Saudi Arabia.
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Abstract
Alzheimer's disease (AD) is a progressive, neurodegenerative disease and the most common form of dementia in elderly people. It is an emerging public health problem that poses a huge societal burden. Linkage analysis was the first milestone in unraveling the mutations in APP, PSEN1, and PSEN2 that cause early-onset AD, followed by the discovery of apolipoprotein E-ε4 allele as the only one genetic risk factor for late-onset AD. Genome-wide association studies have revolutionized genetic research and have identified over 20 genetic loci associated with late-onset AD. Recently, next-generation sequencing technologies have enabled the identification of rare disease variants, including unmasking small mutations with intermediate risk of AD in PLD3, TREM2, UNC5C, AKAP9, and ADAM10. This review provides an overview of the genetic basis of AD and the relationship between these risk genes and the neuropathologic features of AD. An understanding of genetic mechanisms underlying AD pathogenesis and the potentially implicated pathways will lead to the development of novel treatment for this devastating disease.
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Affiliation(s)
- Mohan Giri
- Department of Geriatrics, The First Affiliated Hospital of Chongqing Medical University, Yuzhong District, Chongqing, People’s Republic of China
| | - Man Zhang
- Department of Geriatrics, The First Affiliated Hospital of Chongqing Medical University, Yuzhong District, Chongqing, People’s Republic of China
| | - Yang Lü
- Department of Geriatrics, The First Affiliated Hospital of Chongqing Medical University, Yuzhong District, Chongqing, People’s Republic of China
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Abstract
Cardiac delayed rectifier potassium channels conduct outward potassium currents during the plateau phase of action potentials and play pivotal roles in cardiac repolarization. These include IKs, IKr and the atrial specific IKur channels. In this article, we will review their molecular identities and biophysical properties. Mutations in the genes encoding delayed rectifiers lead to loss- or gain-of-function phenotypes, disrupt normal cardiac repolarization and result in various cardiac rhythm disorders, including congenital Long QT Syndrome, Short QT Syndrome and familial atrial fibrillation. We will also discuss the prospect of using delayed rectifier channels as therapeutic targets to manage cardiac arrhythmia.
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Affiliation(s)
- Lei Chen
- Department of Pharmacology, College of Physicians & Surgeons of Columbia University, 630 West 168th Street, New York, NY 10032, USA
| | - Kevin J Sampson
- Department of Pharmacology, College of Physicians & Surgeons of Columbia University, 630 West 168th Street, New York, NY 10032, USA
| | - Robert S Kass
- Department of Pharmacology, College of Physicians & Surgeons of Columbia University, 630 West 168th Street, New York, NY 10032, USA.
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Abstract
Sudden cardiac death occurs in a broad spectrum of cardiac pathologies and is an important cause of mortality in the general population. Genetic studies conducted during the past 20 years have markedly illuminated the genetic basis of the inherited cardiac disorders associated with sudden cardiac death. Here, we review the genetic basis of sudden cardiac death with a focus on the current knowledge on the genetics of the primary electric disorders caused primarily by mutations in genes encoding ion channels, and the cardiomyopathies, which have been attributed to mutations in genes encoding a broader category of proteins, including those of the sarcomere, the cytoskeleton, and desmosomes. We discuss the challenges currently faced in unraveling genetic factors that predispose to sudden cardiac death in the setting of sequela of coronary artery disease and present the genome-wide association studies conducted in recent years on electrocardiographic parameters, highlighting their potential in uncovering new biological insights into cardiac electric function.
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Affiliation(s)
- Connie R Bezzina
- From the Department of Experimental Cardiology, Academic Medical Center, Amsterdam, The Netherlands (C.R.B., N.L.); Molecular Cardiology, Fondazione Salvatore Maugeri, Pavia, Italy (S.G.P.); and Department of Molecular Medicine, University of Pavia, Pavia Italy (S.G.P.)
| | - Najim Lahrouchi
- From the Department of Experimental Cardiology, Academic Medical Center, Amsterdam, The Netherlands (C.R.B., N.L.); Molecular Cardiology, Fondazione Salvatore Maugeri, Pavia, Italy (S.G.P.); and Department of Molecular Medicine, University of Pavia, Pavia Italy (S.G.P.)
| | - Silvia G Priori
- From the Department of Experimental Cardiology, Academic Medical Center, Amsterdam, The Netherlands (C.R.B., N.L.); Molecular Cardiology, Fondazione Salvatore Maugeri, Pavia, Italy (S.G.P.); and Department of Molecular Medicine, University of Pavia, Pavia Italy (S.G.P.).
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45
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Genetic modulators of the phenotype in the long QT syndrome: state of the art and clinical impact. Curr Opin Genet Dev 2015; 33:17-24. [DOI: 10.1016/j.gde.2015.06.009] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2015] [Revised: 06/23/2015] [Accepted: 06/29/2015] [Indexed: 12/22/2022]
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Li L, Shen C, Yao Z, Liang J, Huang C. Genetic variants of potassium voltage-gated channel genes (KCNQ1, KCNH2, and KCNE1) affected the risk of atrial fibrillation in elderly patients. Genet Test Mol Biomarkers 2015; 19:359-65. [PMID: 26066992 DOI: 10.1089/gtmb.2014.0307] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Atrial fibrillation (AF) is a common type of cardiac arrhythmia and is a major healthcare burden. Around 20% of patients show no obvious clinical manifestations; this can lead to a delay of AF diagnosis and prevention. Genetic mutations are one of the important risk factors for AF. This study aimed to assess the associations between polymorphisms on KCNE1, KCNQ1, and KCNH2 with the risk of AF in a Chinese population. MATERIALS AND METHODS A case-control study comprised of 438 AF patients and 450 controls. The tag single-nucleotide polymorphisms (SNPs) were retrieved in the International HapMap database and Haploview software was used to capture all the polymorphisms on KCNE1, KCNQ1, and KCNH2. DNA was extracted from blood and polymerase chain reaction-based assays were used to genotype polymorphisms of the KCNE1, KCNQ1, and KCNH2 genes. Chi-square test and student t-tests were used to evaluate the differences in the clinical characteristics between AF cases and controls. Odds ratios (OR) and corresponding 95% confidence intervals (CIs) were calculated to assess the association between genetic variants of KCNQ1, KCNH2, KCNE1, and AF risk. RESULTS Among the nine tag SNPs, three were significantly associated with the risk of AF: the rs1805127*G allele on KCNE1, and the rs2283228*C and rs1057128*A alleles on KCNQ1. In contrast, rs1805120*T variant was correlated with lower risk of AF. However, the other five genetic variants (rs2237892, rs2237895, rs2237897, rs2070357, and rs2070356) showed no significant association with AF risk (all p>0.05). CONCLUSIONS Our study suggested that the rs1805127*G allele of KCNE1, and the rs2283228*C and rs1057128*A alleles on KCNQ1 are risk factors for AF, while the rs1805120*T allele on KCNH2 may serve as a protective factor for AF.
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Affiliation(s)
- Li Li
- 1 Department of Geriatrics, Renmin Hospital of Wuhan University , Wuhan, China
| | - Chao Shen
- 2 College of Life Sciences, Wuhan University , Wuhan, China
| | - Zhaohui Yao
- 1 Department of Geriatrics, Renmin Hospital of Wuhan University , Wuhan, China
| | - Jinjun Liang
- 3 Department of Cardiology, Renmin Hospital of Wuhan University , Wuhan, China .,4 Cardiovascular Research Institute, Wuhan University , Wuhan, China
| | - Congxin Huang
- 3 Department of Cardiology, Renmin Hospital of Wuhan University , Wuhan, China .,4 Cardiovascular Research Institute, Wuhan University , Wuhan, China
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A Kinase Anchoring Protein 9 Is a Novel Myosin VI Binding Partner That Links Myosin VI with the PKA Pathway in Myogenic Cells. BIOMED RESEARCH INTERNATIONAL 2015; 2015:816019. [PMID: 25961040 PMCID: PMC4415471 DOI: 10.1155/2015/816019] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/20/2014] [Revised: 11/05/2014] [Accepted: 11/12/2014] [Indexed: 12/13/2022]
Abstract
Myosin VI (MVI) is a unique motor protein moving towards the minus end of actin filaments unlike other known myosins. Its important role has recently been postulated for striated muscle and myogenic cells. Since MVI functions through interactions of C-terminal globular tail (GT) domain with tissue specific partners, we performed a search for MVI partners in myoblasts and myotubes using affinity chromatography with GST-tagged MVI-GT domain as a bait. A kinase anchoring protein 9 (AKAP9), a regulator of PKA activity, was identified by means of mass spectrometry as a possible MVI interacting partner both in undifferentiated and differentiating myoblasts and in myotubes. Coimmunoprecipitation and proximity ligation assay confirmed that both proteins could interact. MVI and AKAP9 colocalized at Rab5 containing early endosomes. Similarly to MVI, the amount of AKAP9 decreased during myoblast differentiation. However, in MVI-depleted cells, both cAMP and PKA levels were increased and a change in the MVI motor-dependent AKAP9 distribution was observed. Moreover, we found that PKA phosphorylated MVI-GT domain, thus implying functional relevance of MVI-AKAP9 interaction. We postulate that this novel interaction linking MVI with the PKA pathway could be important for targeting AKAP9-PKA complex within cells and/or providing PKA to phosphorylate MVI tail domain.
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Porta A, Girardengo G, Bari V, George AL, Brink PA, Goosen A, Crotti L, Schwartz PJ. Autonomic control of heart rate and QT interval variability influences arrhythmic risk in long QT syndrome type 1. J Am Coll Cardiol 2015; 65:367-374. [PMID: 25634836 DOI: 10.1016/j.jacc.2014.11.015] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/30/2014] [Revised: 10/08/2014] [Accepted: 11/04/2014] [Indexed: 11/27/2022]
Abstract
BACKGROUND A puzzling feature of the long QT syndrome (LQTS) is that family members carrying the same mutation often have divergent symptoms and clinical outcomes. OBJECTIVES This study tested the hypothesis that vagal and sympathetic control, as assessed by spectral analysis of spontaneous beat-to-beat variability of RR and QT intervals from standard 24-h electrocardiogram Holter recordings, could modulate the severity of LQTS type 1 (LQT1) in 46 members of a South-African LQT1 founder population carrying the clinically severe KCNQ1 A341V mutation. METHODS Nonmutation carriers (NMCs) (n = 14) were compared with mutation carriers (MCs) (n = 32), 22 with and 10 without major symptoms. We assessed the effect of circadian rhythm and beta-blocker therapy over traditional time and frequency domain RR and QT variability indexes. RESULTS The asymptomatic MCs differed significantly from the symptomatic MCs and from NMCs in less vagal control of heart rate and more reactive sympathetic modulation of the QT interval, particularly during daytime when arrhythmia risk for patients with LQT1 is greatest. CONCLUSIONS The present data identified an additional factor contributing to the differential arrhythmic risk among patients with LQT1 carrying the same mutation. A healthy autonomic control confers a high risk, whereas patients with higher sympathetic control of the QT interval and reduced vagal control of heart rate are at lower risk. This differential "autonomic make-up," likely under genetic control, will allow refinement of risk stratification within families with LQTS, leading to more targeted management.
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Affiliation(s)
- Alberto Porta
- Department of Biomedical Sciences for Health, University of Milan, Milan, Italy; IRCCS Galeazzi Orthopedic Institute, Milan, Italy.
| | - Giulia Girardengo
- Center for Cardiac Arrhythmias of Genetic Origin and Laboratory of Cardiovascular Genetics, IRCCS Istituto Auxologico Italiano, Milan, Italy
| | - Vlasta Bari
- Department of Cardiothoracic, Vascular Anesthesia and Intensive Care, IRCCS Policlinico San Donato, Milan, Italy
| | - Alfred L George
- Department of Pharmacology, Northwestern University Feinberg School of Medicine, Chicago, Illinois; Departments of Medicine and Pharmacology, Vanderbilt University, Nashville, Tennessee
| | - Paul A Brink
- Department of Internal Medicine, University of Stellenbosch, Stellenbosch, South Africa
| | - Althea Goosen
- Department of Internal Medicine, University of Stellenbosch, Stellenbosch, South Africa
| | - Lia Crotti
- Center for Cardiac Arrhythmias of Genetic Origin and Laboratory of Cardiovascular Genetics, IRCCS Istituto Auxologico Italiano, Milan, Italy; Department of Molecular Medicine, University of Pavia, Pavia, Italy
| | - Peter J Schwartz
- Center for Cardiac Arrhythmias of Genetic Origin and Laboratory of Cardiovascular Genetics, IRCCS Istituto Auxologico Italiano, Milan, Italy
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Tiron C, Campuzano O, Pérez-Serra A, Mademont I, Coll M, Allegue C, Iglesias A, Partemi S, Striano P, Oliva A, Brugada R. Further evidence of the association between LQT syndrome and epilepsy in a family with KCNQ1 pathogenic variant. Seizure 2015; 25:65-7. [PMID: 25645639 DOI: 10.1016/j.seizure.2015.01.003] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2014] [Revised: 12/22/2014] [Accepted: 01/04/2015] [Indexed: 11/17/2022] Open
Abstract
PURPOSE Ion channels are expressed both in the heart and in the brain, being advocated as responsible for sudden unexpected death in epilepsy but few pathogenic mutations have been identified. We aim to identify a novel gen associated with channelopathies and epilepsy in a family. METHODS We assessed a family showing epilepsy concomitant with LQTS. Index case showed prolonged QT interval. His father suffers of LQT and epilepsy. We performed a direct sequencing analysis of KCNQ1, KCNH2, KCNE1, KCNE2 and SCN5A genes. RESULTS We identified a non-synonymous heterozygous missense pathogenic mutation (p.L273F) in exon 6 of the KCNQ1 gene. All clinically affected relatives carried the same mutation. CONCLUSION We report, for a first time, a KCNQ1 mutation in a family suffering of both phenotypes, suggesting that KCNQ1 genetic variations may confer susceptibility for recurrent seizure activity increasing the risk or lead to sudden death.
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Affiliation(s)
- Coloma Tiron
- Cardiology Service, Hospital Josep Trueta, Girona, Spain; Cardiology Department, Hospital of Palamós, Palamós, Spain
| | - Oscar Campuzano
- Cardiovascular Genetics Center, Institut d'Investigació Biomèdica de Girona-IDIBGI, Unversitat de Girona, Girona, Spain; Medical Science Department, School of Medicine, University of Girona, Girona, Spain
| | - Alexandra Pérez-Serra
- Cardiovascular Genetics Center, Institut d'Investigació Biomèdica de Girona-IDIBGI, Unversitat de Girona, Girona, Spain
| | - Irene Mademont
- Cardiovascular Genetics Center, Institut d'Investigació Biomèdica de Girona-IDIBGI, Unversitat de Girona, Girona, Spain
| | - Monica Coll
- Cardiovascular Genetics Center, Institut d'Investigació Biomèdica de Girona-IDIBGI, Unversitat de Girona, Girona, Spain
| | - Catarina Allegue
- Cardiovascular Genetics Center, Institut d'Investigació Biomèdica de Girona-IDIBGI, Unversitat de Girona, Girona, Spain
| | - Anna Iglesias
- Cardiovascular Genetics Center, Institut d'Investigació Biomèdica de Girona-IDIBGI, Unversitat de Girona, Girona, Spain
| | - Sara Partemi
- Institute of Public Health Section of Legal Medicine, School of Medicine, Catholic University, Rome, Italy
| | - Pasquale Striano
- Pediatric Neurology and Muscular Diseases Unit, Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health, University of Genova, "G. Gaslini" Institute, Genova, Italy
| | - Antonio Oliva
- Institute of Public Health Section of Legal Medicine, School of Medicine, Catholic University, Rome, Italy
| | - Ramon Brugada
- Cardiology Service, Hospital Josep Trueta, Girona, Spain; Cardiovascular Genetics Center, Institut d'Investigació Biomèdica de Girona-IDIBGI, Unversitat de Girona, Girona, Spain; Medical Science Department, School of Medicine, University of Girona, Girona, Spain.
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