UDP-glucuronosyltransferase 1-4 is an enzyme that in humans is encoded by the<unk>  gene. 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. This enzyme has some glucuronidase activity towards bilirubin, although it is more active on amines, steroids, and sapogenins. It is the main enzyme responsible for glucuronidation of the anticonvulsant lamotrigine.
UGT1A4
UGT2B7
UGT1A8
UGT2B4
UGT1A9
CYP2C19
CYP1A2
CYP3A5