DUX4 and facioscapulohumeral muscular dystrophy: Even though LCLs are not myogenic in nature, only FSHD patient-derived lines express DUX4 (Jones et al., 2017), and the DUX4 transcriptome in LCLs is similar to that in myogenic lineages (Banerji et al., 2020), suggesting that LCLs are appropriate for studying DUX4 expression and activity.