In analogy to symptomatic female dystrophinopathy carriers, our results suggest that heterozygous alpha-sarcoglycan gene mutation carriers can be symptomatic with selective muscle weakness.
We report a family with three affected siblings with a mild phenotype consisting of late onset glutei and axial muscle weakness produced by a new mutation in the SGCA gene leading to a partial expression of the alpha-sarcoglycan protein.
Defect of SGCA was previously shown to lead to severe childhood autosomal recessive muscular dystrophy (LGMD2D) which result in progressive muscle weakness and can also be associated with hyperlordosis or scoliosis.
The sarcoglycan genes should be added to the differential diagnosis for cases that present with rhabdomyolysis, exercise intolerance, and hyperCKemia, even in the absence of muscle weakness or normal α-sarcoglycan immunohistochemistry.