title: Validation of rapid polymerase chain reaction-based detection of all length polymorphisms in the UGT 1A1 gene promoter.
abstract: UDP glucuronosyltransferase (UGT) 1A1 gene promoter polymorphism can affect the expression level of the UGT 1A1 enzyme. The polymorphism consists of an insertion of a TA nucleotide sequence into a (TA)6TAA sequence in the gene promoter resulting in (TA)7TAA (UGT1A1*28). This results in a reduced UGT 1A1 expression with 70% less glucuronidation capacity for bilirubin and other UGT1A1 substrates. Other polymorphisms include (TA)8TAA (UGT1A1*37) and (TA)5TAA (UGT1A1*36). The longer the TA repeats the lower the enzyme expression level. The anticancer agent irinotecan is metabolized to the active SN-38, which is further glucuronidated and detoxified by UGT 1A1. Decreased glucuronidation leads to SN-38 accumulation with severe neutropenia and diarrhea. We have developed a rapid polymerase chain reaction (PCR)-based detection of all length polymorphisms in the UGT 1A1 gene promoter. It uses PCR and DNA fragment analysis using an ABI Genetic Analyzer. Thirty-two blood samples were analyzed for UGT 1A1 promoter polymorphism. We found 2 (TA)(5)TAA/(TA)(5)TAA, 4 (TA)(5)TAA/(TA)(6)TAA, 2 (TA)(5)TAA/(TA)(7)TAA, 9 (TA)(6)TAA/(TA)(6)TAA, 11 (TA)(6)TAA/(TA)(7)TAA, 2 (TA)(7)TAA/(TA)(7)TAA, and 2 (TA)(7)TAA/(TA)(8)TAA in our sample group. To confirm the results, 6 samples with different repeats were also analyzed by DNA sequencing method. This is a rapid and reliable method for analysis of the promoter length polymorphisms of UGT 1A1 gene.
authors.affiliation: Molecular Pathology Laboratory, Department of Pathology, Montefiore Medical Center, Albert Einstien College of Medicine, Bronx, NY 10467, USA.
authors.forename: Chih-Kang
authors.initials: CK
authors.lastname: Huang
authors.forename: Alina
authors.initials: A
authors.lastname: Dulau
authors.forename: Chiao-Ju
authors.initials: CJ
authors.lastname: Su-Rick
authors.forename: Qiulu
authors.initials: Q
authors.lastname: Pan
mesh_terms: D000972:Antineoplastic Agents, Phytogenic / Q000493:pharmacokinetics*; D002166:Camptothecin / Q000031:analogs & derivatives* / Q000493:pharmacokinetics; D004247:DNA / Q000032:analysis; D014453:Glucuronosyltransferase / Q000235:genetics*; D006801:Humans; D000077146:Irinotecan; D016133:Polymerase Chain Reaction / Q000379:methods*; D011110:Polymorphism, Genetic; D011355:Prodrugs / Q000493:pharmacokinetics*; D011401:Promoter Regions, Genetic / Q000235:genetics; D000099148:UGT1A1 Enzyme
chemical_list: D000972:Antineoplastic Agents, Phytogenic; D002166:Camptothecin; D004247:DNA; D014453:Glucuronosyltransferase; D000077146:Irinotecan; D011355:Prodrugs; D000099148:UGT1A1 Enzyme