KCNJ2 and catecholaminergic polymorphic ventricular tachycardia: Since the proband presented with typical CPVT phenotype, although KCNJ2 variants can be the cause of an atypical type of CPVT,(Tester et al., 2006) we next proceeded to conduct pair analysis to detect the presence of CNVs.(Ohno et al., 2014) Read numbers obtained by the targeted panel sequencing were compared between control and the proband, then we found that the read number around exon3 in RYR2 of the proband was apparently reduced compared to that of control (Figure 4b), suggested the presence of CNV, massive exon3 deletion, in the proband.