RBM20 and familial dilated cardiomyopathy: Since the first report on RBM20 as a DCM-related gene [32], a large number of heterozygous missense mutations, mainly located at an arginine-serine-arginine-serine-proline (RSRSP) stretch within the RS-rich region, have been identified in DCM patients [33,34,35], and their pathogenic effects have been recently validated in animal models or by using an induced pluripotent stem cell line [28,36,37,38,39,40,41].