FKRP and qualitative or quantitative defects of protein involved in O-glycosylation of alpha-dystroglycan: To date, mutations in seven genes encoding putative or demonstrated glycosyltransferases have been found to underlie these disorders, collectively known as secondary dystroglycanopathies: Protein-O-mannosyl transferase1 (POMT1; OMIM 607423) [4], Protein-O-mannosyl transferase 2 (POMT2; OMIM 607439) [5], Protein-O-mannose 1,2-Nacetylglucosaminyltransferase1 (POMGnT1; OMIM 606822) [6], Fukutin (OMIM 607440) [7], Fukutin-related protein (FKRP; OMIM 606596) [8], [9], LARGE (OMIM 603590) [10] and Dol-P-Man synthase subunit 3 (DPM3, OMIM 605951) [11].