Naturally occurring mutations in RyR2 have frequently been associated with catecholaminergic polymorphic ventricular tachycardia (CPVT), but also with other phenotypes such as idiopathic ventricular fibrillation (IVF), atrial fibrillation (AF), and cardiomyopathies [6–19]. The gene discussed is RYR2; the disease is catecholaminergic polymorphic ventricular tachycardia.