Contribution of Cardiac Sodium Channel beta-Subunit Variants to Brugada Syndrome

Abstract

Background: Brugada syndrome (BrS) is an inheritable cardiac disease associated with syncope, malignant ventricular arrhythmias and sudden cardiac death. The largest proportion of mutations in BrS is found in the SCN5A gene encoding the alpha-subunit of cardiac sodium channels (Nav1.5). Causal SCN5A mutations are present in 18-30% of BrS patients. The additional genetic diagnostic yield of variants in cardiac sodium channel beta-subunits in BrS patients was explored and functional studies on 3 novel candidate variants were performed.