title: Cardiomyopathy and exercise intolerance in muscle glycogen storage disease 0.
abstract: Storage of glycogen is essential for glucose homeostasis and for energy supply during bursts of activity and sustained muscle work. We describe three siblings with profound muscle and heart glycogen deficiency caused by a homozygous stop mutation (R462-->ter) in the muscle glycogen synthase gene. The oldest brother died from sudden cardiac arrest at the age of 10.5 years. Two years later, an 11-year-old brother showed muscle fatigability, hypertrophic cardiomyopathy, and an abnormal heart rate and blood pressure while exercising; a 2-year-old sister had no symptoms. In muscle-biopsy specimens obtained from the two younger siblings, there was lack of glycogen, predominance of oxidative fibers, and mitochondrial proliferation. Glucose tolerance was normal.
authors.affiliation: Department of Pathology, Sahlgrenska University Hospital, Gothenburg, Sweden.
authors.forename: Gittan
authors.initials: G
authors.lastname: Kollberg
authors.forename: Már
authors.initials: M
authors.lastname: Tulinius
authors.forename: Thomas
authors.initials: T
authors.lastname: Gilljam
authors.forename: Ingegerd
authors.initials: I
authors.lastname: Ostman-Smith
authors.forename: Gun
authors.initials: G
authors.lastname: Forsander
authors.forename: Peter
authors.initials: P
authors.lastname: Jotorp
authors.forename: Anders
authors.initials: A
authors.lastname: Oldfors
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Holme
mesh_terms: D001706:Biopsy; D002312:Cardiomyopathy, Hypertrophic / Q000235:genetics*; D002648:Child; D002675:Child, Preschool; D018389:Codon, Nonsense; D004252:DNA Mutational Analysis; D017079:Exercise Tolerance / Q000235:genetics*; D005260:Female; D005951:Glucose Tolerance Test; D006003:Glycogen / Q000032:analysis*; D006008:Glycogen Storage Disease / Q000235:genetics*; D006006:Glycogen Synthase / Q000172:deficiency / Q000235:genetics*; D006720:Homozygote; D006801:Humans; D008112:Liver Glycogen / Q000032:analysis; D008297:Male; D008928:Mitochondria / Q000378:metabolism; D018482:Muscle, Skeletal / Q000201:enzymology* / Q000473:pathology; D009206:Myocardium / Q000201:enzymology / Q000473:pathology
chemical_list: D018389:Codon, Nonsense; D008112:Liver Glycogen; D006003:Glycogen; D006006:Glycogen Synthase