Glycogen storage disease type IX Glycogen storage disease type IX Glycogen storage disease type IX is a hereditary deficiency of glycogen phosphorylase kinase B that affects the liver and skeletal muscle tissue. It is inherited in an X-linked or autosomal recessive manner. The signs and symptoms in glycogen storage disease type IX include: Most of these signs and symptoms diminish as adulthood sets in. Glycogen storage disease type IX can be inherited via: The diagnosis of glycogen storage disease IX consists of the following: There are two types of this inherited condition, "glycogen storage disease IXa1" and "glycogen storage disease IXa2" that affect the liver
Glycogen debranching enzyme a glycogen branch down to four glucose residues, it will not remove further residues. Glycogen debranching enzymes assist phosphorylase, the primary enzyme involved in glycogen breakdown, mobilize glycogen stores. Phosphorylase can only cleave α-1,4- glycosidic bond between adjacent glucose molecules in glycogen but branches exist as α-1,6 linkages. When phosphorylase reaches four residues from a branching point it stops cleaving; because 1 in 10 residues is branched, cleavage by phosphorylase alone would not be sufficient in mobilizing glycogen stores. Before phosphorylase can resume catabolism, debranching enzymes perform two functions: Thus the debranching enzymes, transferase and α-1,6- glucosidase converts the branched