DUX4 and facioscapulohumeral muscular dystrophy: We and others have reported that AON strategies were effective in down-regulating DUX4 expression in FSHD-derived myoblast cultures (20,24), in a xenograft mouse model carrying muscle biopsies from FSHD patients (29) and as a local intramuscular treatment in a recently developed FLExDUX4 mouse model of FSHD (26,30).