A new muscle glycogen storage disease associated with glycogenin-1 deficiency

Ann Neurol. 2014 Dec;76(6):891-8. doi: 10.1002/ana.24284. Epub 2014 Oct 31.

Abstract

We describe a slowly progressive myopathy in 7 unrelated adult patients with storage of polyglucosan in muscle fibers. Genetic investigation revealed homozygous or compound heterozygous deleterious variants in the glycogenin-1 gene (GYG1). Most patients showed depletion of glycogenin-1 in skeletal muscle, whereas 1 showed presence of glycogenin-1 lacking the C-terminal that normally binds glycogen synthase. Our results indicate that either depletion of glycogenin-1 or impaired interaction with glycogen synthase underlies this new form of glycogen storage disease that differs from a previously reported patient with GYG1 mutations who showed profound glycogen depletion in skeletal muscle and accumulation of glycogenin-1.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Female
  • Glucosyltransferases / deficiency*
  • Glucosyltransferases / genetics
  • Glycogen Storage Disease / diagnosis*
  • Glycogen Storage Disease / genetics
  • Glycogen Storage Disease / metabolism*
  • Glycogen Synthase / metabolism
  • Glycoproteins / deficiency*
  • Glycoproteins / genetics
  • Humans
  • Male
  • Middle Aged
  • Muscle, Skeletal / metabolism*

Substances

  • Glycoproteins
  • glycogenin
  • Glucosyltransferases
  • Glycogen Synthase