CACNA1C and Timothy syndrome: Mutations in CaV1.2 channels are associated with multiple heart diseases including Timothy syndrome that is characterized by a long QT interval and ventricular arrhythmia due to sustained activation of CaV1.2 channels23, 24 and Brugada syndrome that is notable for a short QT interval and sudden cardiac death due to inactivation of CaV1.2 channels25.