β_2肾上腺素能受体基因+491C/T多态性与新疆哈萨克族原发性高血压的关联研究

Association between the+491C/T polymorphism of β_2-adrenergic receptor gene and risk of essential hypertension in Kazakns of Xinjiang

目的研究新疆哈萨克族人β_2肾上腺素能受体(β_2-AR)基因+491C/T 多态性与原发性高血压(EH)的关系,旨在从分子水平探讨哈萨克族人 EH 易感机制。方法采用人群为基础的病例-对照研究方法,选择507例30～60岁哈萨克族人(289例 EH 者与218例血压正常者)为研究对象,酚/氯仿法提取外周血白细胞基因组 DNA,应用 PCR-RFLP 技术,检测+491C/T 基因型,并观察各基因型和等位基因频率在该人群中 EH 组和正常血压组的分布及其差异。结果该人群β_2-AR 基因+491C/T 位点检测出两种基因型 CC、CT,分布频率分别为98.82%、1.18%,等位基因 C、T 频率为99.41%、0.59%,符合 Hardy-Weinberg 平衡(X^2=0.018,P=0.893)。两种基因型频率在 EH 组分别为:97.92%、2.08%,在正常血压组中未发现 CT 基因型;两组中等位基因 C、T 分布频率分别为98.96%、1.04%和100%、0%;两组基因型、等位基因频率的分布差异均有统计学意义(P 均为0.04)。各基因型间收缩压、舒张压差异无统计学意义(P>0.05),但根据性别进行分层后,各基因型间收缩压差异有统计学意义(P=0.046)。结论β_2AR 基因+491C/T 多态性与新疆哈萨克族人尤其是男性哈萨克族人 EH 相关联,提示该多态性可能是哈萨克族人 EH 的易感因素。

Objective To investigated the association between the ＋ 491C/T polymorphism of β2- AR gene and risk of essential hypertension （EH） in Kazakns of Xinjiang. Methods In this populationbased case-control study, we recruited 507 Kazakns subjects （289 EH and 218 normotensives,aged from 30- 60 years old） from the pastoral areas in Xinjiang. Peripheral blood were collected and the DNA was extracted by means of a standard phenol-chloroform method. The ＋ 491C/T genotypes of β2-AR was identified by PCR-restriction fragment length polymorphism analysis. The distribution of genotypic and allelic frequencies between EH and controls were also compared. Results The frequencies of the genotype CC, CT were 98. 82% and 1.18%, respectively and there was no TT genotype in this population, the genotype distribution was consistent with Hardy-Weinberg equilibrium （x^2 = 0. 018, P = 0. 893 ）. CC and CT genotypic frequencies were 97.92% and 2. 08% respectively in EH, while there was no CT genotype in normotensives. The allelic frequencies of C, T were significantly different between EH （98.96%, 1.04% ） and normotensives （100% ,0%, all P =0. 040）. Systolic blood pressure and diastolic blood pressure were similar in subjects with various genotypes in the whole population （ P 〉 0. 05 ） but systolic blood pressure was significantly higher in males with CT genotype compared with males with CC genotype （ P = 0. 046 ）. Condusion The ＋491C/T polymorphism of β2-AR gene is associated with essential hypertension and is a possible susceptible factor for essential hypertension in Kazakns of Xinjiang.