Glycogen storage disease type VI Glycogen storage disease type VI Glycogen storage disease type VI (GSD VI) is a type of glycogen storage disease caused by a deficiency in liver glycogen phosphorylase or other components of the associated phosphorylase cascade system. It is also known as "Hers' disease", after Henri G. Hers, who characterized it in 1959. The scope of GSD VI now also includes glycogen storage disease type VIII, IX (caused by phosphorylase b kinase deficiency) and X (deficiency protein kinase A). The incidence of GSD VI is approximately 1 case per 65,000–85,000 births, representing approximately 30% all cases of glycogen storage disease. Patients
Glycogen storage disease type II Glycogen storage disease type II Glycogen storage disease type II, also called Pompe disease, is an autosomal recessive metabolic disorder which damages muscle and nerve cells throughout the body. It is caused by an accumulation of glycogen in the lysosome due to deficiency of the lysosomal acid alpha-glucosidase enzyme. It is the only glycogen storage disease with a defect in lysosomal metabolism, and the first glycogen storage disease to be identified, in 1932 by the Dutch pathologist J. C. Pompe. The build-up of glycogen causes progressive muscle weakness (myopathy) throughout the body and affects various body tissues, particularly in the