Is there diversity among UGT1A1 polymorphism in Japan

AIM: To investigate into the diversity of UGT1A1 polymorphism across three different districts in Japan and highlight genetic differences among the population in Japan. METHODS: We enrolled 50 healthy volunteers from each of the Yamaguchi (western part of Japan), Kochi (southern part of Japan) and Akita (northern part of Japan) prefectures. Blood samples (7 mL) were collected from each participant and stored in EDTA for subsequent genotyping by fragment size analysis, direct sequencing and TaqMan assay of UGT1A1*28, UGT1A7*3/UGT1A9*22 and UGT1A1*93/UGT1A1*6/UGT1A1*27/UGT1A1*60/UGT1A7 (-57), respectively. RESULTS: The only statistically significant differences in allele polymorphisms among the group examined were for UGT1A1*6. The Akita population showed more UGT1A1*6 heterozygosity (P = 0.0496). CONCLUSION: Our study revealed no regional diversity among UGT1A1, UGT1A7 or UGT1A9 polymorphisms in Japan.