UGT1A1
Chr 2ARADUDP glucuronosyltransferase family 1 member A1
Also known as: BILIQTL1, GNT1, HUG-BR1, UDPGT, UDPGT 1-1, UGT1, UGT1A
The protein is a UDP-glucuronosyltransferase that conjugates lipophilic substrates including bilirubin with glucuronic acid to facilitate their excretion, serving as essential for drug detoxification and elimination of endogenous compounds. Mutations cause Crigler-Najjar syndromes types I and II, Gilbert syndrome, and familial transient neonatal hyperbilirubinemia, with inheritance patterns that can be either autosomal recessive or autosomal dominant depending on the specific condition. The gene shows low constraint against loss-of-function variants (LOEUF 1.331), and these bilirubin metabolism disorders typically present in the neonatal period or early infancy.
Primary Disease Associations & Inheritance
Population Genetics & Constraint
gnomAD v4 — loss-of-function & missense intolerance
Highly tolerant — LoF variants common in population
Tolerant to missense variation
Predictions shown for reference only — model trained on dominant genes, not applicable to AR conditions.
The Badonyi & Marsh prediction model was trained exclusively on dominant disease genes. Predictions are not reliable for genes with autosomal recessive inheritance and are shown at reduced opacity for reference only.
Literature Evidence
Predictions from Badonyi M, Marsh JA. PLoS ONE. 2024;19(8):e0307312.
ClinVar Variant Classifications
0 submitted variants in ClinVar
Protein Context — Lollipop Plot
UGT1A1 · protein map & ClinVar variants
Showing all ClinVar variants across the protein. Search a specific variant to highlight its position.
External Resources
Links to major genomics databases and tools
Clinical Trials
Active and recruiting trials from ClinicalTrials.gov
Clinical Study of Irinotecan Liposome Combination Therapy for Advanced Gastric Cancer
NOT YET RECRUITINGGene Therapy for Severe Crigler Najjar Syndrome
RECRUITINGA Real-world Study of Liposomal Irinotecan (Onivyde)-Based Therapy in Patients With Locally Advanced/Metastatic Pancreatic Cancer in China
NOT YET RECRUITINGPrecision Medicine in the Treatment of Epilepsy
RECRUITINGPreoperative Radiotherapy And ASTX660 in Rectum Cancer
RECRUITINGUGT1A1-Based Irinotecan Therapy for Locally Advanced Rectal Cancer
RECRUITINGHypofractionated Radiotherapy Combined With NALIRIF, PD-1 Antibody in Locally Recurrent Rectal Cancer(NOVELTY-R)
RECRUITINGPharmacogenomics-Supported Psychotropic Prescribing Trial
RECRUITINGSacituzumab Govitecan Plus Bevacizumab in Metastatic TNBC
ENROLLING BY INVITATIONA Study Evaluating the Efficacy of 5-FU + NALIRI and 5-FU + NALIRINOX for PDAC (NALPAC)
RECRUITINGTelecommunication Technology-based Online Survey
RECRUITINGDORAvirine Versus DOlutegravir Based Antiretroviral Regimens in Treatment-naïve People Living With HIV-1 Infection
RECRUITINGExternal Resources
Links to major genomics databases and tools