Glycogen storage disease type 0b

Glycogen storage disease type 0b (GSD-0b), also known as muscle glycogen synthase deficiency, is an autosomal recessive disorder of glycogen metabolism. GSD-0b is caused by mutations in the GYS1 gene, which encodes muscle glycogen synthase. The role of muscle and heart glycogen is to provide critical energy during bursts of activity and sustained muscle work. It has been reported that patients showed muscle fatigability, hypertrophic cardiomyopathy, and an abnormal heart rate and blood pressure while exercising.