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GTR Home > Conditions/Phenotypes > Glycogen storage disease IXd

Glycogen storage disease IXd

Synonyms
GSD IXd; Muscle Phosphorylase Kinase Deficiency; PHKA1-Related Phosphorylase Kinase Deficiency
Modes of inheritance
Autosomal recessive inheritance (Orphanet)
X-linked recessive inheritance (Orphanet)

Summary

Phosphorylase kinase (PhK) deficiency causing glycogen storage disease type IX (GSD IX) results from deficiency of the enzyme phosphorylase b kinase, which has a major regulatory role in the breakdown of glycogen. The two types of PhK deficiency are liver PhK deficiency (characterized by early childhood onset of hepatomegaly and growth restriction, and often, but not always, fasting ketosis and hypoglycemia) and muscle PhK deficiency, which is considerably rarer (characterized by any of the following: exercise intolerance, myalgia, muscle cramps, myoglobinuria, and progressive muscle weakness). While symptoms and biochemical abnormalities of liver PhK deficiency were thought to improve with age, it is becoming evident that affected individuals need to be monitored for long-term complications such as liver fibrosis and cirrhosis. [from GeneReviews]

Available tests

48 tests are in the database for this condition.

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Clinical tests (48 available)

Biochemical Genetics Tests

Molecular Genetics Tests

Genes See tests for all associated and related genes

  • Also known as: PHKA, PHKA1
    Summary: phosphorylase kinase regulatory subunit alpha 1

Clinical features

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Imported from Human Phenotype Ontology (HPO)

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