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UGT1A1 UDP glucuronosyltransferase family 1 member A1

Gene ID: 54658, updated on 4-Nov-2018
Also known as: GNT1; UGT1; UDPGT; UGT1A; HUG-BR1; BILIQTL1; UDPGT 1-1


This gene encodes a UDP-glucuronosyltransferase, an enzyme of the glucuronidation pathway that transforms small lipophilic molecules, such as steroids, bilirubin, hormones, and drugs, into water-soluble, excretable metabolites. This gene is part of a complex locus that encodes several UDP-glucuronosyltransferases. The locus includes thirteen unique alternate first exons followed by four common exons. Four of the alternate first exons are considered pseudogenes. Each of the remaining nine 5' exons may be spliced to the four common exons, resulting in nine proteins with different N-termini and identical C-termini. Each first exon encodes the substrate binding site, and is regulated by its own promoter. The preferred substrate of this enzyme is bilirubin, although it also has moderate activity with simple phenols, flavones, and C18 steroids. Mutations in this gene result in Crigler-Najjar syndromes types I and II and in Gilbert syndrome. [provided by RefSeq, Jul 2008]

Associated conditions

See all available tests in GTR for this gene

Atazanavir response
MedGen: CN417141GeneReviews: Not available
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Bilirubin, serum level of, quantitative trait locus 1
MedGen: C1866173OMIM: 601816GeneReviews: Not available
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Crigler-Najjar syndrome, type II
MedGen: C2931132OMIM: 606785GeneReviews: Not available
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Gilbert's syndrome
MedGen: C0017551OMIM: 143500GeneReviews: Not available
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Irinotecan response
MedGen: CN077989GeneReviews: Not available
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Lucey-Driscoll syndrome
MedGen: C0270210OMIM: 237900GeneReviews: Not available
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Genomic context

Chromosome: 2; NC_000002.12 (233760273..233773299)
Total number of exons:


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