中国南方汉族人群三种代谢酶基因多态性的分布特征

The distributive features of three kinds of metabolic genes polymorphisms in population of Han nationality in south area of China

目的 了解中国南方某汉族人群 3种肿瘤易感代谢酶基因多态性的分布特征。方法 以社区为基础的病例 -对照研究中对照人群为分析对象 ,包括有血缘关系内对照 2 90人和无血缘关系外对照4 0 4人。结果 3种代谢酶基因多态性在性别、居住地区、胃癌家族史、吸烟史等混杂因素中的频率差异均无显著性 ,个别组在年龄、饮酒史中的分布有差异 ,在相关性分析时需调整。 CYP1A1Ile/Val基因型频率为 33.4 3% ,Val/Val为 5 .6 2 % ,与中国人、日本人频率接近 ,但明显高于美洲、欧洲白人及美国黑人 ;GSTM1缺失基因频率为 5 3.4 8% ,在中国人群中也有一定差异 ;GSTT1缺失基因频率为 4 5 .78% ,显著高于白种人和美国黑人。结论 中国南方汉族人 CYP1A1突变基因频率和 GSTT1缺失基因频率高于其它种族 ,而 GSTM1缺失基因频率与其它种族的差异较小。

Objective: To find out the distributive features of some metabolic genes polymorphisms in Han population of south area of China. Methods: Study population was obtained from the controls of a community based case-control study, which included 290 blood relatives (inner control) and 404 non-blood relatives (outer control). Results: Frequencies of CYP1A1, GSTM1 and GSTT1 polymorphisms had no significant difference among confounding factors, such as sex, living areas, stomach cancer family history and history of tobacco smoking etc. Some controls showed significant difference in age group and alcohol drinking which would be adjusted in analysis of the relationship between polymorphisms and cancers. CYP1A1 Ile/Val and Val/Val genotypes were 33.43% and 5.62% respectively, which were similar to other results from Chinese and Japanese, but higher than those from Caucasians in American, Europe and African-Americans. GSTM1 null allele frequency was 53.48% in our population, which showed difference even among Chinese in different areas. GSTT1 null allele frequency was 45.78%, which was significantly higher than that in Caucasians and African-American. Conclusion: The frequencies of CYP1A1 Ile/Val, Val/Val and GSTT1 null in Han population in south area of China are significantly higher than those in other races, while the ethnic difference of frequency of GSTM1 null is less.