A new muscle glycogen storage disease associated with glycogenin-1 deficiency.
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ABSTRACT:
SUBMITTER: Malfatti E
PROVIDER: S-EPMC4348070 | biostudies-literature | 2014 Dec
REPOSITORIES: biostudies-literature
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A new muscle glycogen storage disease associated with glycogenin-1 deficiency.
Malfatti Edoardo E Nilsson Johanna J Hedberg-Oldfors Carola C Hernandez-Lain Aurelio A Michel Fabrice F Dominguez-Gonzalez Cristina C Viennet Gabriel G Akman H Orhan HO Kornblum Cornelia C Van den Bergh Peter P Romero Norma B NB Engel Andrew G AG DiMauro Salvatore S Oldfors Anders A
Annals of neurology 20141031 6
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 g ...[more]
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