Type 4 glycogenosis
A metabolic disorder that is caused by a deficiency of glycogen branching enzyme (i.e. 1,4-alpha-glucan branching enzyme) resulting in the extra glycogen storage in cells, especially of liver, kidney, and muscle tissues
Glycogenosis refers to a group of metabolic disorders due to the improper metabolism of glycogen. It involves certain enzymes that have become defective or deficient and therefore affected glycogen metabolism. The outcome is the excessive deposition of glycogen in cells. There are different types of glycogenosis and one of them is type 4 glycogenosis. This disease is characterized by a deficiency of 1,4-alpha-glucan branching enzyme. Because of this, there is a buildup of abnormal glycogen with long inner and outer chains. This enzyme accumulates in the cells of tissues, especially liver, kidney, and muscle.
Type 4 glycogenosis is inherited in an autosomal recessive pattern. This means that the individual has two copies of the defective gene (i.e. GBE1 gene) and therefore manifests symptoms associated with the disease. A carrier of the disease would have only one copy of the defective gene and therefore may not show symptoms. Some of the common symptoms are hepatomegaly, myopathy, and dilated cardiomyopathy.
- glycogen storage disease type IV (GSD IV)
- Andersons disease
- Glycogen branching enzyme deficiency
- polyglucosan body disease