Fernandez et al. validated this finding for MDX mice (9% eRMS penetrance late in life) and further found that mice deficient for of Alpha-Sarcoglycan (Sgca−/−), mutated in limb girdle muscular dystrophy (LGMD) can also lead to eRMS occurrence late in life (4% penetrance). Here, SGCA is linked to limb-girdle muscular dystrophy.