SCN5A and catecholaminergic polymorphic ventricular tachycardia: First, although several other genes, including TECRL, TRDN, CALM1-3, SCN5A and KCNJ2 apart from RYR2 and CASQ2 have been reported to be associated with CPVT [19]–[21], negative genetic testing is also observed in some cases and other underlying genes and/or variants warrant to be further uncovered.