Muscular dystrophies due to glycosylation defects: diagnosis and therapeutic strategies

Purpose of review Dystroglycanopathies are a common group of diseases characterized by a reduction in alpha-dystroglycan glycosylation. This review discusses the recent novel discovery of additional dystroglycanopathy variants and progress in dystroglycanopathy animal models. Recent findings Several novel glycosyltransferase genes have been found to be responsible for a dystroglycanopathy phenotype, and in addition recessive mutations in DAG1 have been identified for the first time in a primary dystroglycanopathy. Studies in dystroglycanopathy mouse models have clarified some aspects of the structural defects observed in the central nervous system and in the eye, whereas a study in zebrafish implicates unfolded protein response in the pathogenesis of two of the secondary dystroglycanopathies. Summary Improved understanding of the molecular bases of dystroglycanopathies will lead to more precise diagnosis and genetic counseling; therapeutic strategies are being developed and tested in the preclinical models and it is hoped that these observations will pave the way to therapeutic interventions in humans.