2Cardiovascular Diseases, School Of Medicine, Isfahan University Of Medical Sciences; Isfahan- Iran
3Cardiovascular Research Institute, And Genome Institute Of Singapore, Yong Loo Lin School Of Medicine, National University Of Singapore, Singapore- Singapore
4Service Of Medical Genetics, Department Of Laboratories, The University Hospital Of Lausanne; Lausanne- Switzerland
5Electrophysiology Department, Shaheed Rajaei Cardiovascular Medical And Research Center, Tehran University Of Medical Sciences; Tehran- Iran
Abstract
Objective: SCN5A encodes alpha subunit of the major sodium channel (Nav1.5) in human cardiac tissue. Malfunction of this cardiac sodium channel is associated with a variety of cardiac arrhythmias and myocardial inherited diseases.
Materials and Methods: Fifty-three members from three families each diagnosed with long-QT syndrome type 3 (LQTS3), Brugada syndrome (BrS), or sick sinus syndrome (SSS) were included in this observational, cross-sectional study. In this study, we analyzed the sequences of coding region of the SCN5A gene.
Results: Eleven members of the LQTS family (39%) showed p.Gln1507-Lys1508-Pro1509del mutation, 8 of BrS family (50%) showed p.Arg222Ter nonsense mutation, and 5 of 9 SSS family members (55%) showed a novel p.Met1498Arg mutation in the SCN5A gene.
Conclusion: p.Gln1507-Lys1508-Pro1509del mutation, p.Arg222Ter nonsense mutation, and p.Met1498Arg in LQTS, BrS, and SSS, respectively, are reported for the first time in the Iranian population. Information regarding underlying genetic defects would be necessary for verifying certain clinically diagnosed arrhythmia types, carrier screening in affected families, and more precise therapy of the patients are required. (Anatol J Cardiol 2016; 16: 170-4)