Glycogen debranching enzyme (GDE) deficiency, or glycogen storage disease type 3 (GSD 3), is a form of glycogen storage disease characterized by severe muscle weakness and hepatopathy. The disease is glycogen storage disease III (MONDO_0009291). Also known as: AGL glycogen storage disease, Cori disease, Cori-Forbes disease, Forbes disease, GDE deficiency, GSD due to glycogen debranching enzyme deficiency, GSD type 3, GSDIII.