Glycogen storage disease type IV the gene but show no symptoms of the disease. It affects 1 in 800,000 individuals worldwide, with 3% of all Glycogen Storage Diseases being type IV. It is a result of the absence of the glycogen branching enzyme, which is critical in the production of glycogen. This leads to very long unbranched glucose chains being stored in glycogen. The long unbranched molecules have a low solubility which leads to glycogen precipitation in the liver. These deposits subsequently build up in the body tissue, especially the heart and liver. The inability to breakdown glycogen in muscle cells causes muscle weakness. The
Glycogen storage disease type V phenomenon that occurs when muscle is poisoned by iodoacetate, a substance that blocks breakdown of glycogen into glucose and prevents the formation of lactate. Dr. McArdle accurately concluded that the patient had a disorder of glycogen breakdown that specifically affected skeletal muscle. The associated enzyme deficiency was discovered in 1959 by W. F. H. M. Mommaerts et al. Glycogen storage disease type V Glycogen storage disease type V (GSD-V) is a metabolic disorder, more specifically a glycogen storage disease, caused by a deficiency of myophosphorylase. Its incidence is reported as one in 100,000, roughly the same as glycogen storage disease