Clinical, pathologic, and mutational spectrum of dystroglycanopathy caused by LARGE mutations

Academic Article

Abstract

  • Dystroglycanopathies are a subtype of congenital muscular dystrophy of varying severity that can affect the brain and eyes, ranging from Walker-Warburg syndrome with severe brain malformation to milder congenital muscular dystrophy presentations with affected or normal cognition and later onset. Mutations in dystroglycanopathy genes affect a specific glycoepitope on α-dystroglycan; of the 14 genes implicated to date, LARGE encodes the glycosyltransferase that adds the final xylose and glucuronic acid, allowing α-dystroglycan to bind ligands, including laminin 211 and neurexin. Only 11 patients with LARGE mutations have been reported. We report the clinical, neuroimaging, and genetic features of 4 additional patients. We confirm that gross deletions and rearrangements are important mutational mechanisms for LARGE. The brain abnormalities overshadowed the initially mild muscle phenotype in all 4 patients. We present the first comprehensive postnatal neuropathology of the brain, spinal cord, and eyes of a patient with a homozygous LARGE mutation at Cys443. In this patient, polymicrogyria was the predominant cortical malformation; densely festooned polymicrogyria were overlaid by a continuous agyric surface. In view of the severity of these abnormalities, Cys443 may be a functionally important residue in the LARGE protein, whereas the mutation p.Glu509Lys of Patient 1 in this study may confer a milder phenotype. Overall, these results expand the clinical and genetic spectrum of dystroglycanopathy. Copyright © 2014 by the American Association of Neuropathologists, Inc.
  • Authors

    Digital Object Identifier (doi)

    Author List

  • Meilleur KG; Zukosky K; Medne L; Fequiere P; Powell-Hamilton N; Winder TL; Alsaman A; El-Hattab AW; Dastgir J; Hu Y
  • Start Page

  • 425
  • End Page

  • 441
  • Volume

  • 73
  • Issue

  • 5