| Disease Association
|| Defects in GAA are the cause of glycogen storage disease II (GSD-II) (MIM:232300); also known as Pompe disease. GSD-II is an autosomal recessive disorder with a broad clinical spectrum. At one end there are patients presenting at birth with massive accumulation of glycogen in muscle, heart and liver and with a life expectancy of less than two years. Cardiorespiratory insufficiency is the major cause of death in this infantile form of GSD-II. At the opposite end of the spectrum there are patients who are free of clinical symptoms for most of their life but who develop finally a slowly progressive myopathy. Often the first manifestation is a weakness of the limb and girdle muscle, but some patients present respiratory insufficiency first. There is a third clinical phenotype, the juvenile form.