UQCRC2

Chr 16AR

ubiquinol-cytochrome c reductase core protein 2

Also known as: MC3DN5, QCR2, UQCR2

The protein is a core subunit of mitochondrial respiratory chain complex III (ubiquinol-cytochrome c reductase), essential for cellular energy production through oxidative phosphorylation. Biallelic mutations cause mitochondrial complex III deficiency nuclear type 5, inherited in an autosomal recessive pattern. The pathogenic mechanism involves loss of protein function leading to impaired mitochondrial respiration.

GeneReviewsOMIMResearchSummary from RefSeq, OMIM, UniProt, Mechanism
DNmechanismARLOEUF 0.831 OMIM phenotype
Clinical SummaryUQCRC2
🧬
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.
📖
GeneReview available — UQCRC2
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
0.83LOEUF
pLI 0.000
Z-score 2.19
OE 0.52 (0.340.83)
Tolerant

Typical tolerance to LoF variation

Missense Constraint
0.95Z-score
OE missense 0.83 (0.740.93)
207 obs / 249.3 exp
Tolerant

Mild missense constraint

Observed / Expected Ratios
LoF OE0.52 (0.340.83)
00.351.4
Missense OE0.83 (0.740.93)
00.61.4
Synonymous OE0.91
01.21.6
LoF obs/exp: 13 / 24.8Missense obs/exp: 207 / 249.3Syn Z: 0.64
DN
0.7228th %ile
GOF
0.4777th %ile
LOF
0.3745th %ile

The highest-scoring mechanism for this gene is dominant-negative.

DNprediction above median

Note: In-silico variant effect predictors (SIFT, PolyPhen, REVEL, CADD) may underestimate pathogenicity of missense variants in genes with GOF or DN mechanisms. Consider functional evidence and clinical context.

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

ClinVar Variant Classifications

0 submitted variants in ClinVar

Protein Context — Lollipop Plot

UQCRC2 · 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 →