We found no differences in Suv4–20h1 mRNA levels between wild type, FRG1 or FRG1/FHL1 mice, but observed a significant increase in Eid3 mRNA levels and protein expression in FRG1 muscle relative to wild type muscle (S4 E–I Fig.), as previously reported in FRG1 mice and FSHD muscle [35]. The gene discussed is EID3; the disease is facioscapulohumeral muscular dystrophy.