SGCB and autosomal recessive limb-girdle muscular dystrophy type 2E: LGMD type 2E/R4 (LGMD2E/R4) is caused by mutations in the β-sarcoglycan gene (SGCB), leading to β-sarcoglycan (SGCB) protein deficiency and loss of sarcoglycan complex formation and preventing dystrophin-associated protein complex (DAPC) stabilization4,5.