FKRP and neuromuscular disease caused by qualitative or quantitative defects of alpha-dystroglycan: The importance of the O-glycans on α-DG has been illustrated by the discoveries that the mutations in known and putative glycosyl-transferase genes such as POMT1/2, POMGnT1, LARGE, Fukutin, and Fukutin-related protein (FKRP) cause aberrant O-glycosylation of α-DG and result in various muscular dystrophies with a wide spectrum of clinical manifestations (termed as dystroglycanopathies) [5], [6], [7], [8], [9], [10].