TTN and cardiomyopathy: Therefore, because TTN was among the first genes shown to be regulated by RBM20, its connection to DCM, and its importance in cardiac biology, the research focus on RBM20 cardiomyopathy mostly lay on TTN. However, recent findings suggest that RBM20 cardiomyopathy cannot solely be explained by changes in TTN splicing, and that missplicing of additional RBM20 target genes is likely to contribute to the phenotype [11•].