DUX4 and facioscapulohumeral muscular dystrophy: LNA gapmers (against exon 3) and 2′-O-methoxyethyl (2′-MOE) gapmers (against the coding region) reduced DUX4 levels in immortalized FSHD myocytes and following intramuscular delivery to the FLExDUX4 FSHD mouse model [65,66].