Mutations in the TRDN gene have also been implicated in the development of CPVT (Landstrom et al., 2017), which encodes a tripeptide protein, a transmembrane protein located in the intracellular sarcoplasmic reticulum, that interacts with CASQ2, RyR2, and other proteins and is critical for the regulation of Ca2+ stores and release. Here, CASQ2 is linked to catecholaminergic polymorphic ventricular tachycardia.