Component of the sarcoglycan complex, a subcomplex of the dystrophin-glycoprotein complex which forms a link between the F-actin cytoskeleton and the extracellular matrix. Defects in SGCD are the cause of limb-girdle muscular dystrophy type 2F (LGMD2F) [MIM:601287]. LGMD2F is an autosomal recessive disorder. Defects in SGCD are the cause of cardiomyopathy dilated type 1L (CMD1L) [MIM:606685]. Dilated cardiomyopathy is a disorder characterized by ventricular dilation and impaired systolic function, resulting in congestive heart failure and arrhythmia. Patients are at risk of premature death.