COQ5

Chr 12AR

coenzyme Q5, methyltransferase

Also known as: COQ10D9

The COQ5 protein is a methyltransferase required for ubiquinone (coenzyme Q10) biosynthesis, specifically converting 2-decaprenyl-6-methoxy-1,4-benzoquinol to 2-decaprenyl-3-methyl-6-methoxy-1,4-benzoquinol in the mitochondrial inner membrane. Mutations cause primary coenzyme Q10 deficiency 9, which follows autosomal recessive inheritance. This gene has low constraint against loss-of-function variants (pLI 0.00003, LOEUF 0.95), and detailed clinical information is available in GeneReviews.

GeneReviewsOMIMResearchSummary from RefSeq, OMIM, UniProt
DNmechanismARLOEUF 0.951 OMIM phenotype
Clinical SummaryCOQ5
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Gene-Disease Validity (ClinGen)
mitochondrial disease · ARModerate

Moderate evidence — consider for supplementary testing

Population Constraint (gnomAD)
Low constraint (pLI 0.00) — loss-of-function variants are relatively tolerated in the population.
📋
ClinVar Variants
18 unique Pathogenic / Likely Pathogenic· 52 VUS of 92 total submissions
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GeneReview available — COQ5
Authoritative clinical overview · Recommended first read
Open GeneReview ↗

Population Genetics & Constraint

gnomAD v4 — loss-of-function & missense intolerance

Tolerant — LoF & missense variants common in population
LoF Constraint
0.95LOEUF
pLI 0.000
Z-score 1.72
OE 0.56 (0.340.95)
Tolerant

Typical tolerance to LoF variation

Missense Constraint
-0.36Z-score
OE missense 1.08 (0.961.21)
191 obs / 177.4 exp
Tolerant

Tolerant to missense variation

Observed / Expected Ratios
LoF OE0.56 (0.340.95)
00.351.4
Missense OE1.08 (0.961.21)
00.61.4
Synonymous OE0.89
01.21.6
LoF obs/exp: 10 / 17.8Missense obs/exp: 191 / 177.4Syn Z: 0.73
Curated Mechanism (G2P)Gene2Phenotype (DDG2P) ↗
limitedCOQ5-related intellectual developmental disorderOTHERAR

Predictions shown for reference only — model trained on dominant genes, not applicable to AR conditions.

DN
0.74top 25%
GOF
0.5758th %ile
LOF
0.2580th %ile

The Badonyi & Marsh prediction model was trained exclusively on dominant disease genes. Predictions are not reliable for genes with autosomal recessive inheritance and are shown at reduced opacity for reference only.

Predictions from Badonyi M, Marsh JA. PLoS ONE. 2024;19(8):e0307312.

ClinVar Variant Classifications

92 submitted variants in ClinVar

Classification Summary

Pathogenic13
Likely Pathogenic5
VUS52
Likely Benign11
Benign4
Conflicting1
13
Pathogenic
5
Likely Pathogenic
52
VUS
11
Likely Benign
4
Benign
1
Conflicting

Curated Variants Distribution

Classified variants from ClinVar · 5 ACMG categories

ClassificationLoFMissense + InframeNon-codingSynonymousTotal
Pathogenic
0
0
13
0
13
Likely Pathogenic
1
0
4
0
5
VUS
1
46
5
0
52
Likely Benign
0
6
2
3
11
Benign
0
0
2
2
4
Conflicting
1
Total25226586

LoF = frameshift, stop gained/lost, canonical splice · Counts from ClinVar esearch · Updated hourly

View in ClinVar →

Protein Context — Lollipop Plot

COQ5 · protein map & ClinVar variants

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

3D Protein StructureAlphaFold

Clinical Trials

Active and recruiting trials from ClinicalTrials.gov

No active trials found for this gene.

Search ClinicalTrials.gov →
Clinical Literature
Open Research Assistant →