Original ArticlesValidation of Rapid Polymerase Chain Reaction-based Detection of All Length Polymorphisms in the UGT 1A1 Gene PromoterHuang, Chih-Kang MS; Dulau, Alina MD; Su-Rick, Chiao-Ju MS; Pan, Qiulu MD, PhD Author Information Molecular Pathology Laboratory, Department of Pathology, Montefiore Medical Center, Albert Einstien College of Medicine, Bronx, NY 10467 Reprints: Qiulu Pan, MD, PhD, Molecular Pathology Laboratory, Department of Pathology, Montefiore Medical Center, Albert Einstein College of Medicine, Bronx, NY 10467 (e-mail: [email protected]). Diagnostic Molecular Pathology 16(1):p 50-53, March 2007. | DOI: 10.1097/01.pdm.0000213467.91139.c9 Buy Metrics 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)5TAA/(TA)5TAA, 4 (TA)5TAA/(TA)6TAA, 2 (TA)5TAA/(TA)7TAA, 9 (TA)6TAA/(TA)6TAA, 11 (TA)6TAA/(TA)7TAA, 2 (TA)7TAA/(TA)7TAA, and 2 (TA)7TAA/(TA)8TAA 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. © 2007 Lippincott Williams & Wilkins, Inc.