TGFB1 and familial dilated cardiomyopathy: Of note, PR domain containing 16 (PRDM16), a repressor of TGFβ signaling and known genetic cause of left ventricular, non-compaction cardiomyopathy (LVNC) and DCM [1], was significantly downregulated in ACT iPSC CM after DOX, but not in DOX-treated control cells (Fig. 8E).