Enzymes of the UDP glycosyltransferase (UGT; EC 220.127.116.11) superfamily covalently link glycosyl groups to lipophilic substrates. UGT1A enzymes, such as UGT1A7
, efficiently use UDP-glucuronic acid as the glycosyl donor and are invaluable in detoxifying both endogenous and foreign chemicals, because the glycosylated chemical is more water soluble and therefore more readily excreted.
Several UGT1A enzymes, including UGT1A7, are encoded by the UGT1A gene complex on chromosome 2q37. Within this complex, 9 viable first exons are independently spliced to 4 common exons to generate 9 UGT1A transcripts with unique 5-prime ends and identical 3-prime ends. UGT1A7, like each first exon within the UGT1A gene complex, is considered a unique gene linked to the 4 common exons.