SUV39H1 and Facioscapulohumeral dystrophy: However, the above-discussed findings and the role of the genes in maintaining the repressive pressure on the D4Z4 locus suggest that CTCF, DNMT1, DNMT3A, EZH2 and SUV39H1 might be further investigated as genes whose alteration contributes to the permissive (epi)genetic environment required to develop FSHD.