DUX4 and facioscapulohumeral muscular dystrophy: To determine the muscle regenerative potential of PSC-derived myogenic progenitors in the context of DUX4-mediated muscle degeneration, as occurs in FSHD, we transplanted Pax3-induced murine embryonic stem cell (ESC)-derived myogenic progenitors into iDUX4pA-HSA mice.