The most common form of dystroglycanopathy, LGMD2I, is caused by mutations in FKRP; it occurs at a frequency of 1 in 250,000 in the U.S. The use of corticosteroids to reduce fibrosis and muscle loss has shown promise with LGMD2I. This evidence concerns the gene FKRP and neuromuscular disease caused by qualitative or quantitative defects of alpha-dystroglycan.