中文摘要：

目的探讨血清同型半胱氨酸（Hcy）、叶酸（FA）、维生素B12水平及亚甲基四氢叶酸还原酶（MTHFR）基因多态性与脑梗死的相关性。方法选择首都医科大学附属北京天坛医院神经内科住院脑梗死患者70例作为试验组,选择同期来该院进行体检的健康志愿者30例作为健康对照组。并采用循环酶法检测血清Hcy水平,化学发光免疫法检测血清FA、维生素B12水平,采用实时荧光定量PCR检测试验组中血清Hcy高于正常值患者的MTHFR基因多态性。结果试验组中脑梗死患者血清Hcy水平为高水平（≥15μmol/L）的例数有48例,占68.6%。试验组血清Hcy水平为（23.25±8.17）μmmol/L,健康对照组血清Hcy水平为（7.09±2.25）μmmol/L,差异有统计学意义（P〈0.05）。试验组血清FA水平（6.23±2.19）ng/mL、维生素B12水平（329.89±125.79）μmol/L与健康对照组血清FA水平（10.57±5.70）ng/mL、维生素B12水平（598.85±142.56）μmol/L比较,差异均有统计学意义（P〈0.05）。试验组血清Hcy水平与FA及维生素B12水平均呈负相关关系（P〈0.05）。血清高Hcy患者的MTHFR C677T多态位点CC、CT和TT基因型频率分布分别为CC野生型8.0%,TT突变型39.5%,CT突变型52.5%;MTHFR A1298C多态位点基因型频率分布分别为AC突变型33.3%,AA野生型67.3%。结论 MTHFR C677T突变和血清高Hcy水平及脑梗死发病密切相关。

英文摘要：

Objective To investigate correlation of the serum homocysteine（Hcy）,folic acid（FA）,the level of Vitamin B12 and methylenetetrahydrofolate reductase（MTHFR）gene polymorphism with cerebral infarction.Methods Totally 70 cases of cerebral infarction patients in department of neurology,Beijing Tiantan Hospital were selected as the experimental group,30 cases of healthy volunteers were selected as healthy control group.Circulating enzyme method was used to detect the serum Hcy level.The serum levels of FA and Vitamin B12 were detected by chemiluminescence immunoassay,real-time quantitative PCR was used to detect the polymorphism of MTHFR gene in the patients with serum Hcy higher than normal in experimental group.Results The level of serum Hcy in patients with cerebral infarction in the experimental group（48cases,68.6%）was higher than the normal value（≥15μmol/L）,the serum Hcy level of experimental group was（23.25±8.17）mmol/L,the serum Hcy level of the control group was（7.09±2.25）mmol/L,and the difference was statistically significant（P〈0.05）.The serum level of FA in experimental group was（6.23±2.19）ng/mL and Vitamin B12 levels was（329.89±125.79）mol/L,the serum FA level in the healthy control group was（10.57±5.70）ng/mL,the Vitamin B12 levels was（598.85±142.56）mol/L,the differences were statistically significant between the two groups（P〈0.05）.In the experimental group,the levels of serum Hcy were negatively correlated with the levels of FA and Vitamin B12（P〈0.05）.The frequency distributions of MTHFR C677 T CC,CT and TT genotypes in the patients were CC wild type 8.0%,TT mutant 39.5%,and CT 52.5%;the genotype frequency distribution of MTHFR A1298 Cpolymorphism loci were AC mutant 33.3% and AA wild type 67.3%.Conclusion MTHFR C677 T mutation,high serum Hcy levels and the incidence of cerebral infarction is closely related.