TCAP and cardiomyopathy: There are several limitations in this study: (1) the iPSC-induced CMs are not matured as actual human cardiomyocytes; (2) we do not know the exact underlying mechanisms by which telethonin defects cause cardiomyopathy; (3) data were obtained by in vitro experiments, which is different from the actual human heart; (4) we don’t know the exact effects of TCAP KD on changes of cytoskeletal structures.