CYP4B1

Chr 1

cytochrome P450 family 4 subfamily B member 1

Also known as: CYPIVB1, P-450HP

NCBI Gene: 1580ENSG00000142973UniProt: P13584

This gene encodes a member of the cytochrome P450 superfamily of enzymes. The cytochrome P450 proteins are monooxygenases which catalyze many reactions involved in drug metabolism and synthesis of cholesterol, steroids and other lipids. This protein localizes to the endoplasmic reticulum. In rodents, the homologous protein has been shown to metabolize certain carcinogens; however, the specific function of the human protein has not been determined. Multiple transcript variants have been found for this gene. [provided by RefSeq, Jan 2016]

113
ClinVar variants
7
Pathogenic / LP
0.00
pLI score
0
Active trials
Clinical Summary— CYP4B1
⚡
Population Constraint (gnomAD)
Low constraint (pLI 0.00) — loss-of-function variants are relatively tolerated in the population.
📋
ClinVar Variants
7 Pathogenic / Likely Pathogenic· 78 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.
1.10LOEUF
pLI 0.000
Z-score 1.19
OE 0.74 (0.51–1.10)
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.
-0.21Z-score
OE missense 1.03 (0.94–1.14)
312 obs / 301.8 exp
Tolerant

Tolerant to missense variation

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.0.74 (0.51–1.10)
0≤0.351.4
Missense OE?Ratio of observed to expected missense variants. OE ≤ 0.6 = fewer missense variants than expected by chance.1.03 (0.94–1.14)
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.1.05
0≤1.21.6
LoF obs/exp: 18 / 24.3Missense obs/exp: 312 / 301.8Syn Z: -0.40

ClinVar Variant Classifications

113 submitted variants in ClinVar

ClinVar

Classification Summary

Pathogenic5
Likely Pathogenic2
VUS78
Likely Benign6
Benign8
Conflicting1
5
Pathogenic
2
Likely Pathogenic
78
VUS
6
Likely Benign
8
Benign
1
Conflicting

Curated Variants Distribution

Classified variants from ClinVar · 5 ACMG categories

ClassificationLoFMissense + InframeNon-codingSynonymousTotal
Pathogenic
0
0
5
0
5
Likely Pathogenic
0
0
2
0
2
VUS
0
76
2
0
78
Likely Benign
0
3
0
3
6
Benign
1
5
1
1
8
Conflicting
—1
Total184104100

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

View in ClinVar →

Protein Context — Lollipop Plot

CYP4B1 · protein map & ClinVar variants

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

OMIM — Genotype-Phenotype Relationships

1 OMIM entry

OMIM
Clinical Literature
Landmark / reviewRecent case evidence
Key Publications
Landmark & review papers · by relevance
PubMed
Spotlight on CYP4B1.
Röder A et al.·Int J Mol Sci
2023Review
Quantification of CYP2B7, CYP4B1, and CYPOR messenger RNAs in normal human lung and lung tumors.
Czerwinski M et al.·Cancer Res
1994
Human CYP4B1 gene in the japanese population analyzed by denaturing HPLC.
Hiratsuka M et al.·Drug Metab Pharmacokinet
2004
Characteristics of folic acid metabolism-related genes unveil prognosis and treatment strategy in lung adenocarcinoma.
Dong Y et al.·BMC Pulm Med
2025
Long non-coding RNAs: The hidden players in diabetes mellitus-related complications.
Hussein RM·Diabetes Metab Syndr
2023Review
Molecular Functionality of Cytochrome P450 4 (CYP4) Genetic Polymorphisms and Their Clinical Implications.
Jarrar YB et al.·Int J Mol Sci
2019Review
Genetic polymorphism of the human cytochrome P450 CYP4B1: evidence for a non-functional allelic variant.
Lo-Guidice JM et al.·Pharmacogenetics
2002Functional
Genotypic and phenotypic landscapes of 51 pharmacogenes derived from whole-genome sequencing in a Thai population.
Wankaew N et al.·PLoS One
2022
Regulation of early diagnosis and prognostic markers of lung adenocarcinoma in immunity and hypoxia.
Sun K et al.·Sci Rep
2023
Association between cancer risk and drug-metabolizing enzyme gene (CYP2A6, CYP2A13, CYP4B1, SULT1A1, GSTM1, and GSTT1) polymorphisms in cases of lung cancer in Japan.
Tamaki Y et al.·Drug Metab Pharmacokinet
2011Cohort
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