Analysis of the pathogenesis of cardiac Na channelopathies

据报道，编码心脏Na通道的SCN 5A基因突变可引起多种心律失常。我们对婴儿猝死综合征（SIDS）进行了基因筛查，并阐明了SCN 5A突变在日本婴儿中普遍存在，这些婴儿患有危及生命的心律失常，此外，不仅SCN 5A功能获得型调节（长QT综合征3型），而且功能丧失（Brugada综合征）可能是SIDS的致病基础。此外，我们还分析了与心脏钠通道相关的Z盘蛋白TCAP基因在遗传性心律失常患者中的表达。该突变可能通过调节钠电流与心律失常有关。

Mutations in SCN5A gene, encoding cardiac Na channels, are reported to cause a variety of arrhythmias. We performed genetic screening on sudden infant death syndrome (SIDS) and clarified that SCN5A mutations are prevalent in Japanese infants with life threatening arrhythmias, in addition, not only SCN5A gain-of-function type modulation (Long-QT syndrome type 3, but also loss-of-function (Brugada syndrome) may be a pathogenic basis of SIDS. Furthemore, we analysed TCAP gene, a member of Z-disk proteins which associate with the cardiac Na channels, on patients with inherited arrhythmias. The mutation might be associated with cardiac arrhythmias by modulating Na currents.