Figure 1

Differences in muscle strength and morphology between patients homozygous and those compound heterozygous for the L276I mutation. (A) Normalized ankle dorsal flexor force was reduced in L276I compound heterozygous (L276I c.h.) versus homozygous (L276I+/+) patients (*P < 0.003). (B) Immunostaining for the fukutin-related protein (FKRP) substrate, α-dystroglycan (α-DG), showed a uniform presence in the sarcolemma of healthy controls, whereas it varied in homozygous patients, reflecting the heterogeneity of the disease, and was mostly restricted to newly formed fibers and ring fibers in compound heterozygous patients. (C) Compared with normal muscle (control), muscle of both L276 homozygous and compound heterozygous patients displayed internal nuclei, fibrosis and small newly formed regenerating fibers. The heterogeneous nature of the disease was evident for the patients homozygous for the L276I mutation. (B, C) Bars = 50 μm.