Intriguingly, two different reports assign LQTS and CPVT phenotypes to the same mutation (p.N98S) occurring in genes CALM2 (72) and CALM (84), respectively; since the CaM amino acid sequence encoded by the 2 genes is identical, other factors should account for the discrepancy. The gene discussed is CALM3; the disease is catecholaminergic polymorphic ventricular tachycardia.