KCNQ1 and Prolonged QT interval: Two patients had PVs in genes associated with familial hypercholesterolemia (APOB and LDLR), three had PVs in genes associated with arrhythmic right ventricular cardiomyopathy (DSC2, DSG2, and PKP2), and one patient had a PV in KCNQ1, which is associated with long QT syndrome.