In addition, a few patients have been identified with CPVT symptoms but have mutations in the RyR2 luminal modulator protein calsequestrin, Casq2 gene (CPVT2) which is linked to chromosome1p13–p21 but these patients have an autosomal recessive phenotype (Lahat et al., 2001b; Postma et al., 2005; Terentyev et al., 2006). Here, RYR2 is linked to catecholaminergic polymorphic ventricular tachycardia.