Thus, not only is the SRSF3 NMD+ isoform translated in DUX4-expressing cells, its protein product, SRSF3-TR can be detected in both DUX4-expressing MB135-iDUX4 myoblasts and in FSHD patient-derived myotubes. Here, DUX4 is linked to facioscapulohumeral muscular dystrophy.