SGCB and sarcoglycanopathy: DGC-related muscular dystrophies include dystrophinopathies caused by mutations in DMD, sarcoglycanopathies caused by mutations in SGCG, SGCA, SGCB, and SGCD, and dystroglycanopathies caused by mutations in FKRP and other genes associated with the O-mannose glycosylation pathway of α-DG [1–3].