Histopathological analyses of quadriceps muscle sections from DKO mice. (A) H & E-stained quadriceps muscle sections from dysferlin-null, mdx and DKO mice at six months of age. Scale bar: 100 μm. (B) Quantitative analysis of centrally nucleated muscle fibers (CNF) in quadriceps muscles from WT, dysferlin-null, mdx and DKO mice (n = 6 per group) at six months of age. Each group was significantly different from all the other groups. For clarity, significance is shown only for the comparisons with the DKO mice. ***P < 0.001.