The etiologic fraction (EF) of ACM-related diagnoses from truncating variants in PKP2 is significant (0.85 [0.80,0.88], p < 2 × 10−16), increases for ARVC specifically (EF = 0.96 [0.94,0.97], p < 2 × 10−16), and is highest in definite ARVC versus non-ACM individuals (EF = 1.00 [1.00,1.00], p < 2 × 10−16). This evidence concerns the gene PKP2 and Arrhythmogenic right ventricular dysplasia.