POLG2

Chr 17

DNA polymerase gamma 2, accessory subunit

Also known as: HP55, MTDPS16, MTDPS16A, MTDPS16B, MTPOLB, PEOA4, POLG-BETA, POLGB

NCBI Gene: 11232ENSG00000256525UniProt: Q9UHN1

This gene encodes the processivity subunit of the mitochondrial DNA polymerase gamma. The encoded protein forms a heterotrimer containing one catalytic subunit and two processivity subunits. This protein enhances DNA binding and promotes processive DNA synthesis. Mutations in this gene result in autosomal dominant progressive external ophthalmoplegia with mitochondrial DNA deletions.[provided by RefSeq, Sep 2009]

GeneReviewsResearchGenerating clinical summary…

Primary Disease Associations & Inheritance

UniProtProgressive external ophthalmoplegia with mitochondrial DNA deletions, autosomal dominant, 4
UniProtMitochondrial DNA depletion syndrome 16, hepatic type
UniProtMitochondrial DNA depletion syndrome 16B, neuroophthalmic type
1
Active trials
11
Pubs (1 yr)
—
P/LP submissions
—
P/LP missense
1.06
LOEUF
Multiple*
Mechanism· predicted
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GeneReview available — POLG2
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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

gnomAD
Tolerant — LoF & missense variants common in population
LoF Constraint?
1.06LOEUF
pLI 0.000
Z-score 1.32
OE 0.72 (0.50–1.06)
Tolerant

Highly tolerant — LoF variants common in population

Missense Constraint?
-0.35Z-score
OE missense 1.06 (0.96–1.17)
270 obs / 254.4 exp
Tolerant

Tolerant to missense variation

Observed / Expected Ratios?
LoF OE?0.72 (0.50–1.06)
0≤0.351.4
Missense OE?1.06 (0.96–1.17)
0≤0.61.4
Synonymous OE?1.04
0≤1.21.6
LoF obs/exp: 19 / 26.3Missense obs/exp: 270 / 254.4Syn Z: -0.34

ClinVar Variant Classifications

0 submitted variants in ClinVar

ClinVar

Protein Context — Lollipop Plot

POLG2 · protein map & ClinVar variants

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

External Resources

Links to major genomics databases and tools

Franklin by Genoox
AI-powered variant curation and clinical analysis
DECIPHER
Genomic variants and phenotypes in rare disease patients