Homozygous and heterozygous penetrance of a missense CASQ2 variant in a South Asian family

Biallelic clinically-actionable variants in CASQ2 can cause catecholaminergic polymorphic ventricular tachycardia (CPVT), but this study expands the description of ventricular ectopy in patients with heterozygous variants.The clinical risk associated with exercise-induced ectopy in patients with heterozygous variants is still poorly defined. In CPVT due to CASQ2 variants, dual therapy with flecainide and beta-adrenergic receptor blockers is often required for arrhythmia control Detailed family history and phenotype screening is often required to provide additional information for variant classification.We provide those here for the CASQ2 c.1029G>C (p.Trp343Cys) variant.