Glycogen storage disease type 0 Glycogen storage disease type 0 Glycogen storage disease type 0 is a disease characterized by a deficiency in the glycogen synthase enzyme (GSY). Although glycogen synthase deficiency does not result in storage of extra glycogen in the liver, it is often classified as a glycogen storage disease because it is another defect of glycogen storage and can cause similar problems. There are two isoforms (types) of glycogen synthase enzyme; GSY1 in muscle and GSY2 in liver, each with a corresponding form of the disease. Mutations in the liver isoform (GSY2), causes fasting hypoglycemia, high blood ketones, increased free fatty acids
Glycogen branching enzyme position to which they are transferred, the enzyme creates the very characteristic, highly branched glycogen molecule. Mutations in this gene are associated with glycogen storage disease type IV (also known as Andersen's disease) in newborns and with adult polyglucosan body disease. Approximately 40 mutations in the GBE1 gene, most resulting in a point mutation in the glycogen branching enzyme, have led to the early childhood disorder, glycogen storage disease type IV (GSD IV). This disease is characterized by a severe depletion or complete absence of GBE, resulting in the accumulation of abnormally structured glycogen, known as polyglucosan bodies. Glycogen buildup