In addition to dystrophinopathies, many muscle diseases are caused by genetic abnormalities in proteins which form complexes with dystrophin (e.g., dystrophin–glycoprotein complexes [1]), and it has been reported that abnormalities in the same responsible genes as those of MD also cause DCM [2]. The gene discussed is DMD; the disease is neuromuscular disease caused by qualitative or quantitative defects of dystrophin.