中文摘要：

目的研究血管紧张素原（AGT）基因多态性位点M235T、A-6G、A-20C及其单倍型（M235T-A-6GA-20C）与中国部分原发性高血压（EH）高发的少数民族（蒙古族、哈萨克族、藏族）EH易感性的关系,比较AGT对不同民族人群EH发病风险的影响。方法应用聚合酶链反应（PCR）及限制性片段长度多态性（RFLP）技术判定基因型,采用Haploview软件进行单倍型分布分析。结果哈萨克族EH组-6G分布显著高于对照组（42.34%vs 36.98%,P=0.009）。藏族EH组20C分布显著低于对照组（18.17%vs 23.19%,P=0.038）。哈萨克族EH组M-A-A的分布频率显著低于对照组（38.16%vs 47.50%,P=0.001）,而EH组M-G-A分布频率显著高于对照组（16.20%vs 8.61%,P=0.000）。藏族EH组T-A-A分布频率显著高于对照组（71.89%vs 64.15%,P=0.006）。结论 AGT多态性与EH的相关性具有显著的种族异质性,M235T、A-6G、A-20C与中国蒙古族EH发病风险无关,-6G与哈萨克族EH易感性升高相关,而20A可能降低藏族EH的发病风险;单倍型M-G-A和T-A-A可能分别与哈萨克族和藏族EH易感性升高相关,而M-A-A可能是哈萨克族抗EH的保护性因素。

英文摘要：

【Objective】 To study the association between angiotensinogen gene（AGT） polymorphic site M235 T, A-6G, A-20 C and the haplotype（M235T-A-6G-A-20C） and the susceptibility to essential hypertension（EH） in a part of high-risk minorities in China including Mongolian, Kazakh and Tibetan, and to compare the effect of AGT gene variations on EH in different minorities. 【Methods】 The polymorphisms were genotyped by polymerase chain reaction-restriction fragment length polymorphism（PCR-RFLP）, the haplotype distribution was analyzed by Haploview software. 【Results】 In single locus study, the distribution of-6G was significantly higher in the EH subjects than in the normal subjects（42.34% vs 36.98%, P = 0.009） in Kazakhs; the distribution of-20 C was significantly lower in the EH subjects than in the normal subjects（18.17% vs 23.19%, P = 0.038） in Tibetans. In haplotype analysis, the distribution of M-A-A was significantly lower in the EH subjects than in the normal subjects（38.16% vs 47.50%, P = 0.001） in Kazakhs, while the distributions of M-G-A and T-A-A were significantly higher in the EH subjects than in the normal subjects in Kazakhs and Tibetans, respectively（M-G-A： 16.20% vs 8.61%, P = 0.000; T-A-A： 71.89% vs 64.15%, P =0.006）. 【Conclusions】 The correlation between AGT polymorphisms and EH has showed significant ethnic heterogeneity. M235 T, A-6G and A-20 C are not associated with the susceptibility to EH in Mongolian population.-6G is associated with the increased risk of EH in Kazakhs;-20 C may decrease the risk of EH in Tibetans. Haplotype M-G-A and T-A-A may increase the genetic susceptibility to EH in Kazakhs and Tibetans, respectively, and M-A-A may be a protective haplotype for Kazakhs.