甲烯四氢叶酸还原酶基因多态性与糖尿病大血管病变的关系研究

目的探讨甲烯四氢叶酸还原酶(MTHFR)基因C677T位碱基突变与2型糖尿病患者同型半胱氨酸(Hcy)水平和糖尿病大血管病变的关系。方法将患者分为对照组、糖尿病颈动脉内中膜厚度(IMT)正常组、糖尿病IMT增厚组。应用酶联免疫法测定Hcy水平,采用多聚酶链反应-限制性内切酶片段长度多态性技术(PCR-RFLP)检测MTHFRC677T基因型,用高分辨彩色多普勒检查颈动脉内中膜厚度(IMT)。结果糖尿病IMT增厚组MTHFR基因的TT基因型和T等位基因频率显著增高,与糖尿病IMT正常组及对照组存在统计学差异(P<0.05)。对照组与糖尿病IMT正常组之间T等位基因频率无统计学差异。MTHFR基因突变者血浆Hcy增高。糖尿病组MTHFR基因突变者IMT值明显高于无基因突变者。结论糖尿病IMT增厚组T等位基因频率增高。MTHFR基因C677T点突变组血浆Hcy水平升高,颈动脉IMT增厚。推测MTHFR基因C677T点突变可能是糖尿病合并大血管病变发病的重要遗传因素。

Relationship between genetic polymorphisms of methylenetetrahydrofolate reductase and macrovascular diseases in type 2 diabetes

Objective Aim To investigate genetic polymorphisms of methylenetetrahydrofolate re-ductase(MTHFR) C677T related to macrovascular diseases in type 2 diabetic patients.Methods Thesubjects were divided into 3 groups:diabetes with normal IMT,diabetics with thicked IMT and controlgroups.Plasma Hcy levels were measured by ELISA.MTHFR genetic C677Tpolymorphism was determinedby PCR-RFLP,carotid intimal-medial wall thickness was determined with the use of the doppler ultra-sonography.Results The genotype frequency of diabetics with thicked IMTwas different from that of dia-betic patients with normal IMT and control groups (P<0.05).Plama homocysteine levels were marklyhigher in patients with MTHFR genetic mutation than those in patients without mutation in each group.IMTof MTHFR genetic mutation were thicker than those in patients without mutation in diabetic group.Conclu-sion The frequency of Tallete were statistically higher in diabetics with thicked IMTpatients.Mutation ofMTHFR can cause the elevation of plasma homocysteine level and thicked IMT.We confer that the muta-tion of MTHFR C677Tmay be an important factor for macroangiopathy in diabetics.