EPHX1
Epoxide Hydrolase 1, Microsomal (Xenobiotic-Metabolizing Enzyme)
Gene Information Card
| Symbol | EPHX1 |
|---|---|
| Full Name | Epoxide Hydrolase 1 |
| Gene Type | protein-coding |
| Chromosomal Location | 1q42.12 |
| NCBI Gene ID | 2052 ncbi.nlm.nih.gov/gene/2052 |
| Ensembl ID | ENSG00000143819 |
| UniProt ID | P07099 |
| OMIM ID | 132810 |
| HGNC ID | 3401 |
| Aliases | EPHX, EPHX1L, MEH, mEH |
Description
EPHX1 encodes microsomal epoxide hydrolase, a key biotransformation enzyme that catalyzes the hydrolysis of reactive epoxides to less toxic dihydrodiols. It plays a critical role in the detoxification of xenobiotics and endogenous epoxide substrates, and genetic variants influence susceptibility to chemical-induced toxicity and cancer.
Disease Associations
| Disease category | Pathophysiological mechanism | Genomic evidence |
|---|---|---|
| Epoxide-related toxicity | Reduced detoxification of reactive epoxides due to loss-of-function variants | ClinVar, NCBI |
| Lung cancer | Altered enzyme activity from polymorphic variants (e.g., Tyr113His, His139Arg) modulates risk | OMIM, NCBI |
| Colorectal cancer | Association with EPHX1 low-activity haplotypes | NCBI, COSMIC |
| Fetal hydantoin syndrome | Impaired metabolism of phenytoin epoxide intermediate | OMIM |
Expression Profile
Tissue Expression
| Tissue | nTPM | level |
|---|---|---|
| Liver | 32.5 | High |
| Kidney | 12.1 | Medium |
| Lung | 8.3 | Medium |
| Small intestine | 6.7 | Medium |
| Adrenal gland | 5.4 | Low |
Cell Line Expression
| Cell Line | nTPM | Notes |
|---|---|---|
| HepG2 | 28.9 | Hepatocellular carcinoma cell line |
| A549 | 10.2 | Lung adenocarcinoma cell line |
| HEK293 | 7.5 | Embryonic kidney cell line |
| Caco-2 | 6.1 | Colorectal adenocarcinoma cell line |
Data source：Human Protein Atlas（proteinatlas.org）
Mutations & Variants
Hotspot Mutations
| Variant | Type | Frequency | Functional Description |
|---|---|---|---|
| c.337T>C (Tyr113His) | Missense | ~35% in European populations | Reduced enzyme activity (slow allele) |
| c.416A>G (His139Arg) | Missense | ~25% in European populations | Increased enzyme activity (fast allele) |
| c.337T>C; c.416A>G | Haplotype | Variable | Combined effect on activity; risk modifier |
Mutation functional classification
Loss of Function (LOF)
Tyr113His variant reduces catalytic efficiency toward certain epoxides.
Gain of Function (GOF)
His139Arg variant increases hydrolysis rate for some substrates.
Dominant Negative (DN)
No evidence for dominant-negative effects.
View complete mutation data：
Gene Ontology (GO)
| • epoxide hydrolase activity | • xenobiotic metabolic process |
| • cellular response to toxic substance | • endoplasmic reticulum membrane |
Pathways
• Xenobiotic metabolism by cytochrome P450
• Metabolism of xenobiotics by cytochrome P450 (Reactome R-HSA-211981)
Protein Summary
Microsomal epoxide hydrolase (mEH) is a 455-amino-acid membrane-bound enzyme localized to the endoplasmic reticulum. It adopts an alpha/beta hydrolase fold and uses a catalytic triad (Asp226, His431, Glu404) to hydrolyze a broad range of epoxides. The enzyme is essential for detoxifying environmental carcinogens and drugs, and its polymorphic variants are associated with altered cancer risk.
Related Services
Related Products
| Product name | Cat.No. | Species | Gene ID | |
|---|---|---|---|---|
| EPHX1 Knockout HEK293 Cell Line | EDJ-KQ1069 | Human | 2052 | Details Get a Quote |
| EPHX1 Knockout A-549 Cell Line | EDJ-KQ20204 | Human | 2052 | Details Get a Quote |
| EPHX1 Knockout HeLa Cell Line | EDJ-KQ20205 | Human | 2052 | Details Get a Quote |
| EPHX1 Knockout HCT 116 Cell Line | EDJ-KQ18859 | Human | 2052 | Details Get a Quote |
