As the expression of the FRG1 gene is misregulated in FSHD cells (Figure 2), we investigated whether the D4Z4 contraction affects loop formation by making the same 3C analysis of FSHD myoblasts and myotubes, but we did not find any significant differences from controls (Figure 5b). The gene discussed is FRG1; the disease is Facioscapulohumeral dystrophy.