For example, primary dystroglycanopathies result from a mutation in the Dg gene per se (DAG1 in vertebrates), while deficiencies in 17 genes encoding the enzymes involved in Dg glycosylation have been identified and associated with secondary dystroglycanopathies [4, 5]. This evidence concerns the gene DAG1 and neuromuscular disease caused by qualitative or quantitative defects of alpha-dystroglycan.