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Reviewed August 2015
What is the official name of the PHKA2 gene?
The official name of this gene is “phosphorylase kinase, alpha 2 (liver).”
PHKA2 is the gene's official symbol. The PHKA2 gene is also known by other names, listed below.
Read more about gene names and symbols on the About page.
What is the normal function of the PHKA2 gene?
The PHKA2 gene provides instructions for making one piece, the alpha subunit, of the phosphorylase b kinase enzyme. This enzyme is made up of 16 subunits, four each of the alpha, beta, gamma, and delta subunits. (Each subunit is produced from a different gene.) The alpha subunit helps regulate the activity of phosphorylase b kinase. This enzyme is found in various tissues, although it is most abundant in the liver and muscles. One version of the enzyme is found in liver cells and another in muscle cells. The alpha-2 subunit produced from the PHKA2 gene is part of the enzyme found in the liver.
Phosphorylase b kinase plays an important role in providing energy for cells. The main source of cellular energy is a simple sugar called glucose. Glucose is stored in muscle and liver cells in a form called glycogen. Glycogen can be broken down rapidly when glucose is needed, for instance to maintain normal levels of glucose in the blood between meals. Phosphorylase b kinase turns on (activates) another enzyme called glycogen phosphorylase b by converting it to the more active form, glycogen phosphorylase a. When active, this enzyme breaks down glycogen.
How are changes in the PHKA2 gene related to health conditions?
Where is the PHKA2 gene located?
Cytogenetic Location: Xp22.2-p22.1
Molecular Location on the X chromosome: base pairs 18,892,298 to 18,984,362
(Homo sapiens Annotation Release 107, GRCh38.p2) (
The PHKA2 gene is located on the short (p) arm of the X chromosome between positions 22.2 and 22.1.
More precisely, the PHKA2 gene is located from base pair 18,892,298 to base pair 18,984,362 on the X chromosome.
See How do geneticists indicate the location of a gene? in the Handbook.
Where can I find additional information about PHKA2?
You and your healthcare professional may find the following resources about PHKA2 helpful.
You may also be interested in these resources, which are designed for genetics professionals and researchers.
What other names do people use for the PHKA2 gene or gene products?
See How are genetic conditions and genes named? in the Handbook.
Where can I find general information about genes?
The Handbook provides basic information about genetics in clear language.
These links provide additional genetics resources that may be useful.
What glossary definitions help with understanding PHKA2?
You may find definitions for these and many other terms in the Genetics Home Reference Glossary.
See also Understanding Medical Terminology.
References (6 links)
The resources on this site should not be used as a substitute for professional medical care or advice. Users seeking information about a personal genetic disease, syndrome, or condition should consult with a qualified healthcare professional. See How can I find a genetics professional in my area? in the Handbook.