In these FSHD myotubes, the expression levels of the human DUX4 target genes—ZSCAN4, TRIM43, and MBD3L2 [13,14,16]—were decreased by MT-DUX4-ASO with the IC50 values of 180 nM, 89 nM, and 108 nM, respectively (p < 0.025; Williams’ test) (Figure 1E), indicating its potency in patient muscle cells. Here, MBD3L2 is linked to facioscapulohumeral muscular dystrophy.