How many people are affected by glycogen storage disease type III ?
The incidence of GSDIII in the United States is 1 in 100,000 individuals. This condition is seen more frequently in people of North African Jewish ancestry; in this population, 1 in 5,400 individuals are estimated to be affected.  GSDIIIa is the most common form of GSDIII, accounting for about 85 percent of all cases. GSDIIIb accounts for about 15 percent of cases. GSD types IIIc and IIId are very rare, and their signs and symptoms are poorly defined. Only a small number of affected individuals have been suspected to have GSD types IIIc and IIId.