In the Netherlands, approximately 15% of idiopathic dilated cardiomyopathy (DCM) patients and approximately 12% of arrhythmogenic right ventricular cardiomyopathy (ARVC) patients carry a single pathogenic variant, p.Arg14del (c.40_42delAGA), in the PLN gene that encodes the phospholamban protein, a regulator of cardiomyocyte calcium cycling (Fig. 1; [1]). The gene discussed is PLN; the disease is familial dilated cardiomyopathy.