Abstract:

Objective To investigate the correlation between plasma homocysteine (Hcy) metabolism enzyme 5,10-methylenetetrahydrofolate reductase C677T gene polymorphism and carotid atherosclerosis in patients with cerebral infarction. Methods The newly onset anterior circulation of large artery atherosclerotic infarction patients were enrolled into study group and patients without cerebral infarction during the clinical physical examination were taken as the control group. The level of plasma Hcy was measured by fluorescence polarization immunoassay; color Doppler ultrasound examination of two groups of bilateral extracranial carotid artery atherosclerosis was used to determine whether there was a plaque and the nature of the plaque; and automatic gene chip was used to detect target population MTHFR C677T gene type. Results A total of 150 patients with newly onset anterior circulation cerebral infarction were enrolled into the study group and 100 cases were enrolled in the control group. ①The frequency  of C677T MTHFR mutation (TT) genotype and T allele in the cerebral infarction group were significantly higher than that in the control group (48.0% vs 19.0%, χ 2=22.067, P <0.001; 64.0% vs 45.5%, χ 2=6.907, P =0.009); ②The mutation of C677T C MTHFR and T gene in cerebral infarction group was positively correlated with the degree of carotid artery atherosclerosis stenosis (r =0.353, P <0.001); ③The frequency of C677T MTHFR mutation (TT) genotype and T allele were significantly higher in the unstable plaque group than in the stable plaque group in the cerebral infarction group (66.2% vs 34.1%, χ 2=14.587, P <0.001; 77.5% vs 60.2%, χ 2=6.978, P =0.008) . Conclusion MTHFR T gene mutation in C677T C site may be the risk factor of carotid atherosclerotic plaque instability and stenosis degree.

Key words: Carotid atherosclerosis; Gene polymorphism; Homocysteine; Plasma

摘要：

目的 探讨血浆同型半胱氨酸（h o m o cy ste i n e，H cy）代谢酶5，10 -亚甲基四氢叶酸还原酶（5， 10-methylenetetrahydrofolate reductase，MTHFR）C677T基因多态性与脑梗死患者颈动脉粥样硬化的相 关性。 方法 纳入新发前循环大动脉粥样硬化性脑梗死组患者，以无脑梗死的门诊体检者作为对照组。用 荧光偏振免疫法测定两组血浆Hcy水平，彩色多普勒超声进行双侧颈动脉颅外段检查明确是否存在 动脉粥样硬化斑块及斑块性质，采用全自动基因芯片检测目标人群MTHFR C677T基因型。 结果 共纳入新发前循环脑梗死组患者150例，对照组100例。①脑梗死组MTHFR C677T突变（TT） 基因型及T等位基因频率显著高于对照组（48.0% vs 19.0%，χ 2=22.067，P <0.001；64.0% vs 45.5%， χ 2=6.907，P =0.009）；②脑梗死组MTHFR C677T C→T基因突变与颈动脉粥样硬化狭窄程度呈正 相关（r =0.353，P <0.001）；③脑梗死组中不稳定斑块组MTHFR C677T突变（TT）基因型及T等位基 因频率显著高于稳定斑块组（66.2% vs 34.1%，χ 2=14.587，P <0.001；77.5% vs 60.2%，χ 2=6.978， P =0.008）。 结论 MTHFR C677T位点C→T基因突变是颈动脉粥样硬化斑块不稳定性及其狭窄程度的相关危险 因素。

关键词: 颈动脉粥样硬化; 基因多态性; 同型半胱氨酸; 血浆