In particular, FSHD region gene 1 (FRG1), but not the nearby FRG2 or ANT1 (also known as SLC25A4) (Box 1), showed FSHD-like pathology and impaired muscle growth when overexpressed in mouse (Feeney et al., 2015; Gabellini et al., 2006; Xynos et al., 2013). This evidence concerns the gene FRG1 and facioscapulohumeral muscular dystrophy.