Genetic variants and haplotypes of the UGT1A9, 1A7 and 1A1 genes in Chinese Han.

In this report, we describe combined polymorphisms of the UGT1A9, UGT1A7 and UGT1A1 genes in 100 unrelated, healthy Chinese Han subjects. The functional regions of these genes were sequenced and comprehensively analyzed for genetic polymorphisms. Thirty variants were detected, including five novel forms. Tentative functional predictions indicated that a Cys → Arg substitution at position 277 in the UGT1A7 gene could alter the protein conformation and that 12460T > G in the 3'UTR might influence protein translation through specifically expressed miRNAs. UGT1A9*1b was a major functional variant in the subjects examined whereas the *1f allele had a frequency of only 0.5%. A special functional haplotype (GAGAAC) was identified for UGT1A9, 1A7 and 1A1. These findings provide fundamental genetic information that may serve as a basis for larger studies designed to assess the metabolic phenotypes associated with UGT1A polymorphisms. They also provide important data for the implementation of personalized medicine in Chinese Han.