It is well known that myogenic regulatory factors encoded by the Myod1 family of genes have pivotal roles in myogenesis, with partially overlapping functions, as demonstrated for the mouse embryo. Myogenin-mutant mice, however, exhibit severe myogenic defects without compensation by other myogenic factors. MYOGENIN might be expected to have an analogous function in human myogenic cells. To verify this hypothesis, we generated MYOGENIN-mutated human iPS cells by using CRISPR/Cas9 genome-editing technology. Our results suggest that MYOD1-independent or MYOD1-dependent mechanisms can compensate for the loss of MYOGENIN and that these mechanisms are likely to be crucial for regulating skeletal muscle differentiation and formation.