Clinical And Mutation Analysis Of Glycogen Storage Disease Type Ⅲ

Background and Objective:Type III glycogen storage disease (GSD-III, MIM 232400), is a rare autosomal recessive disorder. The disease also known as Cori's or Forbe's disease, results from a deficiency of the enzyme, amylo-1, 6-glucosidase, 1, 4-alpha- glucano- transferase enzyme (glycogen debrancher enzyme, GDE or amyloglucosidase, AGL), which is responsible for the debranching of the glycogen molecule during catabolism. The clinical manifestations of GSD-III are represented by hepatomegaly, recurrent hypoglycemia, seizures, growth failure, hyperlipidemia, raised transaminases and creatine kinase concentrations and, in a number of subjects, myopathy and cardiomyopathy. The hepatocellular adenoma, hepatocellular carcinoma, diabetes mellitus and liver fibrosis remain rare events. The diagnosis of GSD-III was established by laboratory tests, electromyogram, and muscle and liver biopsy. GSD-III is divided into two subtypes: IIIa and IIIb. In GSD-IIIb, glycogen accumulates only in the liver, whereas both liver and muscles are involved in GSD-IIIa.The AGL gene is located on chromosome 1p21 and contains 35 exons translated in a monomeric protein product. The analysis of the AGL gene by single-strand conformation polymorphism (SSCP), DNA sequencing , restriction analysis and family studies, revealed more than 51 different mutations now. But there is no mutational hot spot.The present study focused on the clinical characteristics and mutation...