Mutations in SCN5A, the gene encoding Nav1.5, are associated with a myriad of clinical syndromes, including Brugada syndrome (BrS), cardiac conduction disease (CCD), long QT syndrome type 3 (LQT3), atrial fibrillation, and dilated cardiomyopathy [2,3]. The gene discussed is SCN5A; the disease is atrial fibrillation.