FKRP and neuromuscular disease caused by qualitative or quantitative defects of alpha-dystroglycan: Despite the vast clinical spectrum, all FKRP-associated diseases share a common biochemical defect, hypoglycosylation of α-dystroglycan (α-DG), and therefore are commonly referred to as dystroglycanopathies (Mercuri et al., 2003; Michele et al., 2002; Muntoni et al., 2002).