As DUX4-toxicity is associated with its full length isoform expression in skeletal muscle [25], directly targeting DUX4 expression to achieve an asymptomatic state in FSHD patients has been carried out by restoring the epigenetic repression of the D4Z4 region or targeting DUX4 expression at its transcriptional level [26,27,28,29]. Here, DUX4 is linked to facioscapulohumeral muscular dystrophy.