The heterotetrameric sarcoglycan complex, composed of α-, β-, γ-, and δ-sarcoglycans, is an
important component of the dystrophin-associated glycoprotein assembly in striated muscle.
Mutations in any of the four genes encoding sarcoglycans cause a deficiency in all
sarcoglycans in the sarcolemma and produce one of four types of limb-girdle muscular
dystrophy. A fifth widely expressed sarcoglycan, ε-sarcoglycan, has been recently described.
ε-Sarcoglycan is homologous to α-sarcoglycan, but whether it associates with the other …