亚甲基四氢叶酸还原酶基因多态性对高血压患者冠心病发病的影响

Clinical study on effect of common methylenetetrahydrofolate reductase gene mutation on coronary artery disease in hypertension

目的 了解亚甲基四氢叶酸还原酶 (methylenetetrahydrofolatereductase ,MTHFR)基因的C6 77T突变对于高血压患者冠心病发病的作用。方法 所有入选的高血压病患者均行冠状动脉 (冠脉 )造影检查。冠脉造影正常 4 5例 (对照组 ) ,冠心病 5 8例 (病例组 )。使用高效液相色谱仪分析测定血浆同型半胱氨酸 (homocysteine,HCY) ,同时应用放射免疫法测定血浆叶酸水平 ,并采用聚合酶链反应 (PCR)检测MTHFR基因型。结果 MTHFR基因的T等位基因频率在冠心病组和对照组分别为0 45和 0 33(P =0 0 3)。MTHFR基因TT基因型与冠心病显著相关。冠心病组血浆HCY水平明显高于对照组 (1 7 73± 2 2 2 μmol/L比 1 2 1 8± 1 2 3μmol/L ,P =0 0 37) ,但两组叶酸水平差异无统计学意义。结论 TT型MTHFR可导致血浆HCY浓度升高 ,并且成为高血压患者发生冠心病的独立危险因素。

Objective To investigate the association between the MTHFR gene C677T mutation and CAD in patients with hypertension. Methods Of the 103 cases of patients with hypertension who underwent coronary angiography, 58 were CAD and 45 were not. MTHFR genotypes were identified by PCR and restriction fragment length polymorphism analysis with Hinf I digestion. Plasma folate was determined by radioimmunoassay. Plasma HCY was determined by HPLC. Results The frequencies of T677 allele (0.45) in the CAD group were markedly higher than those in the control group (0.33, P=0.03), plasma homocysteine level in the CAD group (17.73±2.22 μmol/L) was also significantly higher than that in the control group (12.18±1.23 μmol/L, P=0.037). There was no significant difference in the concentrations of folate for the two studied groups. Conclusion The MTHFR gene T677 variant is the genetic high risk factor for CAD in patients with hypertension. It can induce the hyperhomocysteinemia, potentially contributing to the pathogeny of CAD.