UQCRQ

Chr 5AR

ubiquinol-cytochrome c reductase complex III subunit VII

Also known as: MC3DN4, QCR8, QP-C, QPC, UQCR7

NCBI Gene: 27089ENSG00000164405UniProt: O14949

This gene encodes a ubiquinone-binding protein of low molecular mass. This protein is a small core-associated protein and a subunit of ubiquinol-cytochrome c reductase complex III, which is part of the mitochondrial respiratory chain. [provided by RefSeq, Jul 2008]

Primary Disease Associations & Inheritance

Mitochondrial complex III deficiency, nuclear type 4MIM #615159
AR
113
ClinVar variants
15
Pathogenic / LP
0.05
pLI score
0
Active trials
Clinical Summary— UQCRQ
🧬
Gene-Disease Validity (ClinGen)
Leigh syndrome · ARLimited

Limited evidence — not for standalone diagnostic reporting

⚡
Population Constraint (gnomAD)
Low constraint (pLI 0.05) — loss-of-function variants are relatively tolerated in the population.
📋
ClinVar Variants
15 Pathogenic / Likely Pathogenic· 60 VUS of 113 total submissions

Population Genetics & Constraint

gnomAD v4 — loss-of-function & missense intolerance

gnomAD
Tolerant — LoF & missense variants common in population
LoF Constraint?LOEUF (Loss-of-function Observed/Expected Upper bound Fraction) is the upper bound of the 90% CI for LoF OE — the preferred gnomAD v4 metric. Lower = more intolerant to LoF. LOEUF < 0.35 = highly constrained.
1.69LOEUF
pLI 0.048
Z-score 0.63
OE 0.62 (0.25–1.69)
Tolerant

Highly tolerant — LoF variants common in population

Missense Constraint?Missense Z-score: standard deviations fewer missense variants observed vs. expected. Z > 3.09 (p < 0.001) = gene does not tolerate missense variation. OE missense < 0.6 is also considered constrained.
0.42Z-score
OE missense 0.83 (0.65–1.08)
42 obs / 50.3 exp
Tolerant

Mild missense constraint

Observed / Expected Ratios?Shaded band = 90% confidence interval. Vertical tick = point estimate. Grey threshold line = gnomAD constraint cutoff for that variant class.
LoF OE?Ratio of observed to expected LoF variants. Upper CI bound (LOEUF) ≤ 0.35 = strong LoF constraint signal.0.62 (0.25–1.69)
0≤0.351.4
Missense OE?Ratio of observed to expected missense variants. OE ≤ 0.6 = fewer missense variants than expected by chance.0.83 (0.65–1.08)
0≤0.61.4
Synonymous OE?Control metric — synonymous variants are largely neutral and expected near OE = 1.0. Significant deviation may indicate annotation issues.1.12
0≤1.21.6
LoF obs/exp: 2 / 3.2Missense obs/exp: 42 / 50.3Syn Z: -0.43

ClinVar Variant Classifications

113 submitted variants in ClinVar

ClinVar

Classification Summary

Pathogenic14
Likely Pathogenic1
VUS60
Likely Benign19
Benign9
Conflicting10
14
Pathogenic
1
Likely Pathogenic
60
VUS
19
Likely Benign
9
Benign
10
Conflicting

Curated Variants Distribution

Classified variants from ClinVar · 5 ACMG categories

ClassificationLoFMissense + InframeNon-codingSynonymousTotal
Pathogenic
0
0
14
0
14
Likely Pathogenic
0
0
1
0
1
VUS
2
21
37
0
60
Likely Benign
0
1
8
10
19
Benign
0
0
9
0
9
Conflicting
—10
Total2226910113

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

View in ClinVar →

Protein Context — Lollipop Plot

UQCRQ · protein map & ClinVar variants

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

Gene2Phenotype Curations

UQCRQ-related mitochondrial respiratory chain complex III deficiency

strong
ARUndeterminedAltered Gene Product Structure
Dev. Disorders
G2P ↗
missense variantinframe deletioninframe insertion

Gene2Phenotype curations · DECIPHER consortium patient cohort (public variants) · deciphergenomics.org

OMIM — Genotype-Phenotype Relationships

1 OMIM entry

OMIM

Mitochondrial complex III deficiency, nuclear type 4

MIM #615159

Molecular basis of disorder known

Autosomal recessive
📖
GeneReview available — UQCRQ
Authoritative clinical overview · NCBI Bookshelf · Recommended first read
Open GeneReview ↗
Clinical Literature
Landmark / reviewRecent case evidence
Key Publications
Landmark & review papers · by relevance
PubMed
Identification and mechanistic analysis of shared biomarkers and pathogenesis in acute pancreatitis and sepsis based on differential gene expression and protein interaction networks.
Lu W et al.·Funct Integr Genomics
2025
Mitochondrial complex III deficiency associated with a homozygous mutation in UQCRQ.
Barel O et al.·Am J Hum Genet
2008
Integration of Bioinformatics and Experiments to Identify Mitochondrial Metabolism and Immune Infiltration Characterization in Lung Injury and Post-Injury Lung Fibrosis.
Chen CC et al.·FASEB J
2026
The Association Between Dexmedetomidine and Bradycardia: An Analysis of FDA Adverse Event Reporting System (FAERS) Data and Transcriptomic Profiles.
Morris R et al.·Genes (Basel)
2025
Quantitative proteomics identified 3 oxidative phosphorylation genes with clinical prognostic significance in gastric cancer.
Su F et al.·J Cell Mol Med
2020
Phenotypic variation of TTC19-deficient mitochondrial complex III deficiency: a case report and literature review.
Mordaunt DA et al.·Am J Med Genet A
2015Review
Top 10 resultsSearch PubMed ↗
Recent Gene-Specific Literature
Gene in title · MEDLINE · newest first
Europe PMC
Top 5 resultsSearch Europe PMC ↗

Clinical Trials

Active and recruiting trials from ClinicalTrials.gov

ClinicalTrials.gov

No active trials found for this gene.

Search ClinicalTrials.gov →

External Resources

Links to major genomics databases and tools