Gene SGCA
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Also known as
Sarcoglycan Alpha, ADL, DAG2, DMDA2, LGMD2D, LGMDR3Overview
SGCA (Sarcoglycan Alpha) encodes the alpha subunit of the sarcoglycan complex, a group of transmembrane proteins that form part of the dystrophin-glycoprotein complex (DGC) in muscle cells. This complex spans the muscle cell membrane and provides a crucial structural link between the cytoskeleton inside the cell and the extracellular matrix outside, helping to maintain muscle fiber integrity during contraction. The sarcoglycan complex consists of four subunits (alpha, beta, gamma, and delta) that work together to stabilize the muscle membrane and protect it from damage during repeated cycles of muscle contraction and relaxation.Mutations in SGCA cause limb-girdle muscular dystrophy type 2D (LGMD2D), also known as LGMDR3, an autosomal recessive disorder characterized by progressive weakness and wasting of the proximal muscles of the shoulders and hips. The condition typically presents in childhood or adolescence with difficulty climbing stairs, running, and rising from a seated position. Unlike Duchenne muscular dystrophy, LGMD2D generally progresses more slowly, though severity can vary. Affected individuals may also develop cardiomyopathy and respiratory complications as the disease progresses. Early diagnosis through genetic testing is important for clinical management, cardiac monitoring, and genetic counseling for affected families.