PHKA1

Chr X

phosphorylase kinase regulatory subunit alpha 1

Also known as: PHKA

Phosphorylase kinase is a polymer of 16 subunits, four each of alpha, beta, gamma and delta. The alpha subunit includes the skeletal muscle and hepatic isoforms, and the skeletal muscle isoform is encoded by this gene. The beta subunit is the same in both the muscle and hepatic isoforms, and encoded by one gene. The gamma subunit also includes the skeletal muscle and hepatic isoforms, which are encoded by two different genes. The delta subunit is a calmodulin and can be encoded by three different genes. The gamma subunits contain the active site of the enzyme, whereas the alpha and beta subunits have regulatory functions controlled by phosphorylation. The delta subunit mediates the dependence of the enzyme on calcium concentration. Mutations in this gene cause glycogen storage disease type 9D, also known as X-linked muscle glycogenosis. Alternatively spliced transcript variants encoding different isoforms have been identified in this gene. A pseudogene has been found on chromosome 1.[provided by RefSeq, Feb 2010]

GeneReviewsResearchGenerating clinical summary…

Primary Disease Associations & Inheritance

UniProtGlycogen storage disease 9D

Clinical highlights

Gene-disease validity (ClinGen)
glycogen storage disease IXd · XLDefinitivesufficient evidence for diagnostic panels
0
Active trials
12
Pubs (1 yr)
P/LP submissions
P/LP missense
0.55
LOEUF
Multiple*
Mechanism· predicted
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GeneReview available — PHKA1
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Some data sources returned errors (1)

omim: Error: OMIM fetch failed: 429

Population Genetics & Constraint

gnomAD v4 — loss-of-function & missense intolerance

Moderate LoF intolerance
LoF Constraint?
0.55LOEUF
pLI 0.000
Z-score 4.33
OE 0.38 (0.270.55)
Moderately constrained

More LoF-intolerant than ~75% of genes

Missense Constraint?
1.88Z-score
OE missense 0.76 (0.690.83)
363 obs / 478.8 exp
Tolerant

Mild missense constraint

Observed / Expected Ratios?
LoF OE?0.38 (0.270.55)
00.351.4
Missense OE?0.76 (0.690.83)
00.61.4
Synonymous OE?1.05
01.21.6
LoF obs/exp: 22 / 57.4Missense obs/exp: 363 / 478.8Syn Z: -0.55

ClinVar Variant Classifications

0 submitted variants in ClinVar

Protein Context — Lollipop Plot

PHKA1 · protein map & ClinVar variants

Showing all ClinVar variants across the protein. Search a specific variant to highlight its position.

Clinical Trials

Active and recruiting trials from ClinicalTrials.gov

No active trials found for this gene.

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