Interestingly, a downregulated expression level of CASP9 was observed in DMD iPSC-CMs when compared with control iPSC-CMs (Fig. 4C, middle panel; supplementary material Fig. S4), indicating that the cleavage of UC-CASP3 in DMD iPSC-CMs could be possibly mediated by other caspase(s). The gene discussed is CASP9; the disease is Duchenne muscular dystrophy.