糖尿病视网膜病MTHFR基因多态性及其与血浆同型半胱氨酸水平的关系  

The relationship of methylenetetrahydrofolate reductase gene polymorphism and plasma homocysteine levels in type 2 diabetes mellitus patients with diabetic retinopathy

作　　者：孙家忠[1] 徐焱成[1] 朱宜莲[1] 鲁红云[1] 邓浩华[1] 范幼筠[1] 孙苏欣[1] 张颖[1] 

机构地区：[1]武汉大学中南医院内分泌科,430071

出　　处：《中华医学遗传学杂志》2003年第2期131-134,共4页Chinese Journal of Medical Genetics

摘　　要：目的　研究亚甲基四氢叶酸还原酶 (methylenetetrahydrofolatereductase ,MTHFR)基因多态性及血浆同型半胱氨酸水平与 2型糖尿病视网膜病的关系。方法　应用聚合酶链反应 限制性内切酶片段长度多态性技术检测 2 0 8例 2型糖尿病患者 (其中 110例伴视网膜病 )及 5 7名正常对照的MTHFRC677T基因型 ,采用高效液相色谱法测定血浆同型半胱氨酸水平。结果　糖尿病视网膜病组MTHFR基因TT纯合基因型、CT杂合基因型及T等位基因频率 (分别为 2 8.18%、41.82 %、49.0 9% )均明显高于糖尿病不伴视网膜病组 (分别为 18.3 7%、2 9.5 9%、3 3 .16% )及正常对照组 (分别为 17.5 4%、2 8 0 7%、3 1.5 8% ) ,基因型和等位基因频率分布差异均有显著性 (P <0 .0 1) ,而MTHFR基因多态性在糖尿病不伴视网膜病组与正常对照组之间差异无显著性 (P >0 .0 5 ) ,T等位基因与糖尿病视网膜病的发生密切相关 (OR =1.94,95 %CI :1.3 12 .88)。糖尿病视网膜病组、糖尿病不伴视网膜病组及正常对照组中 ,MTHFR基因有C677T突变者血浆同型半胱氨酸水平均显著高于无基因突变者。结论　MTHFR基因C677T位碱基突变致血浆同型半胱氨酸水平升高可能是糖尿病视网膜病发病的重要遗传因素。Objective: To evaluate the role of methylenetetrahydrofolate reductase (MTHFR) gene polymorphisms and plasma homocysteine levels in Chinese patients with type 2 diabetes mellitus and diabetic retinopathy (DR). Methods: MTHFR genetic C677T polymorphisms was determined by PCR-restriction fragment length polymorphism. Total plasma homocysteine levels were measured using high-performance liquid chromatography (HPLC) with fluorescence detection. Results: The frequencies of MTHFR T homogenetic type and CT heterogenetic type and allele T (28.18%, 41.82%, 49.09%) in type 2 diabetic patients with diabetic retinopathy were significantly higher than those in diabetic patients without retinopathy (18.37%, 29.59%, 33.16%) or the normal controls (17.54%, 28.07%, 31.58%). Howerver, there were no significant differences in the frequency of MTHFR genotype and allele between the type 2 diabetic patients without retinopathy and the normal controls. The presence of T allele appeared to have a strong association with the development of diabetic retinopathy. The odds ratio was 1.94 and the 95% confidence interval was 1.31-2.88. Moreover, the plasma homocysteine levels in patients with TT or CT genotype were markedly higher than those in patients with CC genotype. Conclusion: MTHFR gene C677T mutation associated with a predisposition to increase of plasma homocysteine may represent a genetic risk factor for diabetic retinopathy in Chinese type 2 diabetes mellitus.

关 键 词：糖尿病视网膜病 亚甲基四氢叶酸还原酶 基因多态性 同型半胱氨酸 

分 类 号：R587.2[医药卫生—内分泌] R774.1[医药卫生—内科学]