Only 3.2% of Q133H progenitors and 6.7% of Δ95–99 progenitors fused to form mature myotubes (Figure 5A,C; p < 0.02), demonstrating a massive failure in myotube formation and maturation in these EDMD-causing emerin mutants. The gene discussed is EMD; the disease is Emery-Dreifuss muscular dystrophy.