POR

Chr 7AR

cytochrome p450 oxidoreductase

Also known as: CPR, CYPOR, P450R

This gene encodes an endoplasmic reticulum membrane oxidoreductase that is essential for multiple metabolic processes, including reactions catalyzed by cytochrome P450 proteins for metabolism of steroid hormones, drugs and xenobiotics. The encoded protein has a flavin adenine dinucleotide (FAD)-binding domain and a flavodoxin-like domain which bind two cofactors, FAD and FMN, that allow it to donate electrons directly from NADPH to all microsomal P450 enzymes. Mutations in this gene cause a complex set of disorders, including apparent combined P450C17 and P450C21 deficiency, amenorrhea and disordered steroidogenesis, congenital adrenal hyperplasia and Antley-Bixler syndrome, that resemble those caused by defects in steroid metabolizing enzymes such as aromatase, 21-hydroxylase, and 17 alpha-hydroxylase. [provided by RefSeq, Aug 2020]

OMIMResearchGenerating clinical summary…

Primary Disease Associations & Inheritance

Antley-Bixler syndrome with genital anomalies and disordered steroidogenesisMIM #201750
AR
Disordered steroidogenesis due to cytochrome P450 oxidoreductaseMIM #613571

Clinical highlights

Gene-disease validity (ClinGen)
Antley-Bixler syndrome with genital anomalies and disordered steroidogenesis · ARDefinitivesufficient evidence for diagnostic panels
7
Active trials
1931
Pubs (1 yr)
P/LP submissions
P/LP missense
0.84
LOEUF
GOF
Mechanism· predicted

Population Genetics & Constraint

gnomAD v4 — loss-of-function & missense intolerance

Tolerant — LoF & missense variants common in population
LoF Constraint?
0.84LOEUF
pLI 0.000
Z-score 2.31
OE 0.58 (0.410.84)
Tolerant

Typical tolerance to LoF variation

Missense Constraint?
-0.07Z-score
OE missense 1.01 (0.931.09)
448 obs / 443.7 exp
Tolerant

Tolerant to missense variation

Observed / Expected Ratios?
LoF OE?0.58 (0.410.84)
00.351.4
Missense OE?1.01 (0.931.09)
00.61.4
Synonymous OE?1.06
01.21.6
LoF obs/exp: 21 / 35.9Missense obs/exp: 448 / 443.7Syn Z: -0.67

ClinVar Variant Classifications

0 submitted variants in ClinVar

Protein Context — Lollipop Plot

POR · protein map & ClinVar variants

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

Clinical Trials

Active and recruiting trials from ClinicalTrials.gov

MenopauseGut MicrobiomeHormonal Changes

AGEWISE: Unravelling the Gut-Hormone Axis in Women's Ageing

RECRUITING
NCT07614542Gulbenkian Institute for Molecular MedicineStarted 2025-06-02
Amyloidosis, Hereditary, Transthyretin-Related

Exercise in Hereditary ATTR (ATTRv) Amyloidosis

RECRUITING
NCT07033715Phase NAUniversity of MaiaStarted 2024-10-01
Exercise
Focal Dermal Hypoplasia (FDH)Goltz Syndrome

Study of Selected X-linked Disorders: Goltz Syndrome

ACTIVE NOT RECRUITING
NCT00691223Baylor College of MedicineStarted 2007-06
Colorectal Cancer (CRC)MicrobiomeEarly Onset Colorectal Cancer

CARE-CRC: Microbiome Insights and Correlations for Risk and Outcomes in Colorectal Cancer

RECRUITING
NCT06734156Gulbenkian Institute for Molecular MedicineStarted 2026-03-02
No intervention: observational study
Neuroendocrine NeoplasmNeuroendocrine Neoplasm of Gastrointestinal TractNeuroendocrine Neoplasm of Lung

Genetic Bases of Neuroendocrine Neoplasms in Mexican Patients

RECRUITING
NCT06523582Universidad Nacional Autonoma de MexicoStarted 2022-08-03
Neoplasms

A Study of Encorafenib Plus Cetuximab With or Without Chemotherapy in People With Previously Untreated Metastatic Colorectal Cancer

ACTIVE NOT RECRUITING
NCT04607421Phase PHASE3PfizerStarted 2020-12-21
EncorafenibCetuximabOxaliplatin
Carcinoma, Non-Small-Cell Lung

A Real World Study of Participants With Non-Small Cell Lung Cancer (NSCLC) With Epidermal Growth Factor Receptor Mutation (EGFRm)

NOT YET RECRUITING
NCT07680907Janssen-Cilag Farmaceutica Ltda.Started 2026-10-31