CACNA1C and bipolar disorder: Loss- or gain-of-function mutations in the CACNA1C gene, encoding the α1C (Cav1.2) L-type Ca2+ channel subunit, are associated with a pleiotropic set of disorders including the autism spectrum disorder (ASD) Timothy Syndrome, bipolar disorder, schizophrenia, and major depressive disorder (MDD), as well as severe cardiac defects 63–68.