# UGT1A1

Source: https://onco.cc/targets/ugt1a1/  
OnCo record `ugt1a1` (Target). Data CC BY-NC 4.0, attribute "Data from OnCo (onco.cc)"; commercial use needs a licence.

## TL;DR

UGT1A1 (UDP-glucuronosyltransferase 1A1) is an enzyme. The public catalogues list it as a drug target and a biomarker, and an approved or late-stage drug is recorded against it.

## Summary

UDP-glucuronosyltransferase (UGT) that catalyses phase II biotransformation reactions in which lipophilic substrates are conjugated with glucuronic acid to increase the metabolite's water solubility, thereby facilitating excretion into either the urine or bile. Essential for the elimination and detoxification of drugs, xenobiotics and endogenous compounds. Catalyses the glucuronidation of endogenous oestrogen hormones such as estradiol, estrone and estriol.

CIViC holds 2 clinical evidence items and 0 assertions across 2 variants, naming Belinostat. In OnCo, 1 product record names it (Irinotecan (and liposomal irinotecan)).

## Fields

- Kind: Target
- Last checked: 2026-09-23
- Also known as: UDP glucuronosyltransferase family 1 member A1; UDP-glucuronosyltransferase 1A1; UGT1A; UGT1; GNT1
- Tags: cancer-genes-wave
- Symbol: UGT1A1
- Class: enzyme
- Biology: UDP-glucuronosyltransferase (UGT) that catalyses phase II biotransformation reactions in which lipophilic substrates are conjugated with glucuronic acid to increase the metabolite's water solubility, thereby facilitating excretion into either the urine or bile. Essential for the elimination and detoxification of drugs, xenobiotics and endogenous compounds. Catalyses the glucuronidation of endogenous oestrogen hormones such as estradiol, estrone and estriol. Involved in the glucuronidation of bilirubin, a degradation product occurring in the normal catabolic pathway that breaks down heme in vertebrates. Involved in the glucuronidation of arachidonic acid (AA) and AA-derived eicosanoids including 15-HETE, 20-HETE, PGB1 and F2-isoprostane (8-iso-PGF2alpha). Involved in the glucuronidation of the phytochemical ferulic acid at the phenolic or the carboxylic acid group. Location: Endoplasmic reticulum membrane; Cytoplasm, perinuclear region (UniProt). Locus 2q37.1 (HGNC).

## Notes

- Written by scripts/fetch-cancer-genes.ts from CIViC, Open Targets, IntOGen, HGNC and UniProt; the function text is UniProt's, condensed and in UK spelling. Roles: CIViC lists 1 therapies; CIViC holds 2 clinical evidence items on its variants. Evidence tier "approved-drug" is the strongest of those signals.
- Prevalence not recorded: none of the sources gives a positivity rate.

## Sources

- HGNC HGNC:12530: https://www.genenames.org/data/gene-symbol-report/#!/hgnc_id/HGNC:12530
- UniProt P22309: https://www.uniprot.org/uniprotkb/P22309/entry
- NCBI Gene 54658: https://www.ncbi.nlm.nih.gov/gene/54658
- Ensembl ENSG00000241635: https://www.ensembl.org/Homo_sapiens/Gene/Summary?g=ENSG00000241635

## Connected records

- collections: [CIViC](https://onco.cc/collections/civic/)
- drugs: [Irinotecan (and liposomal irinotecan)](https://onco.cc/drugs/irinotecan/)
- trials: [Combination Chemotherapy and Bevacizumab in Treating Patients With Metastatic Colorectal Cancer](https://onco.cc/trials/nct00628810/), [G-CSF in Preventing Neutropenia During First-Line Treatment With Chemotherapy and Bevacizumab in Patients With Metastatic Colorectal Cancer](https://onco.cc/trials/nct00541125/), [High-dose FOLFIRI in Advanced Colorectal Cancer Patients With Wild-type UGT1A1*6 and *28](https://onco.cc/trials/nct03329183/)

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JSON: https://onco.cc/api/v1/entities/ugt1a1.json