Novel detection assay by PCR???RFLP and frequency of the CYP3A5 SNPs, CYP3A5 *3 and *6, in a Japanese population

Abstract

In this study, we established useful and reliable methods for the direct detection of the variants of CYP3A5 gene by polymerase chain reaction (PCR) and Dde I restriction analysis. The frequency of CYP3A5 related SNPs in 200 healthy Japanese male subjects was determined. The homozygous wild-type (*1/*1) frequency was 7.0% (14/200), the heterozygous (*1/*3) frequency was 32.5% (65/200) and the homozygous mutant-type (*3/*3) frequency was 60.5% (121/200). The *6 allele was not detected in any of the Japanese individuals. This result suggests that an estimated 40% of the Japanese express relatively high levels of metabolically active CYP3A5 protein. The proposed detection assays are useful for screening the CYP3A5 related SNPs in pharmacogenetic research.