Cardiomyopathy and exercise intolerance in muscle glycogen storage disease 0.
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.
Kollberg
Gittan
G
Department of Pathology, Sahlgrenska University Hospital, Gothenburg, Sweden.
Tulinius
Már
M
Gilljam
Thomas
T
Ostman-Smith
Ingegerd
I
Forsander
Gun
G
Jotorp
Peter
P
Oldfors
Anders
A
Holme
Elisabeth
E
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
D018389:Codon, Nonsense; D008112:Liver Glycogen; D006003:Glycogen; D006006:Glycogen Synthase