Majority of CPVT cases arise from mutations in the gene coding for cardiac ryanodine receptor, RYR2. Other genes are also implicated in CPVT, but in far lesser extent, for example, ANK2, CALM1, CALM2, CASQ2, KCNJ2, SCN5A, TECRL, and TRDN [2]. The gene discussed is CALM1; the disease is catecholaminergic polymorphic ventricular tachycardia.