Sun Jiazhong, Xu Yancheng, Zhu Yilian, Lu Hongyun, Deng Haohua, Fan Youyun, Sun Suxin, Zhang Ying
Department of Endocrinology, Zhongnan Hospital, Wuhan University, Wuhan 430071, China.
Chin Med J (Engl). 2003 Jan;116(1):145-7.
To evaluate the role of methylenetetrahydrofolate reductase (MTHFR) gene polymorphisms and plasma homocysteine levels in patients with type 2 diabetes mellitus and diabetic retinopathy (DR).
Total of 208 patients with type 2 diabetes mellitus and 57 controls were recruited into the study. MTHFR genetic C677T polymorphisms were determined by PCR-RFLP. Plasma total homocysteine levels were measured using high-performance liquid chromatography (HPLC) with fluorescence detection.
The frequencies of MTHFR TT homogeneous type, CT heterogeneous type and allele T (28.18%, 41.82%, 49.09%) were significantly higher in the type 2 diabetes mellitus with diabetic retinopathy group than those without retinopathy (18.37%, 29.59%, 33.16%) and those of controls (17.54%, 28.07%, 31.58%). The presence of the T allele appeared to have a strong association with the development of diabetic retinopathy. The odds ratio was 1.94 with a 95% confidence interval of 1.31 - 2.88. Moreover, plasma homocysteine levels were remarkably higher in patients with TT or CT genotype than in patients with the CC genotype.
MTHFR gene C677T mutation associated with a predisposition to increased plasma homocysteine levels may be considered as a genetic risk factor for diabetic microangiopathy (such as DR) in Chinese patients with type 2 diabetes mellitus.
评估亚甲基四氢叶酸还原酶（MTHFR）基因多态性及血浆同型半胱氨酸水平在2型糖尿病及糖尿病视网膜病变（DR）患者中的作用。
共纳入208例2型糖尿病患者及57例对照者进行研究。采用聚合酶链反应-限制性片段长度多态性（PCR-RFLP）法检测MTHFR基因C677T多态性。采用高效液相色谱（HPLC）荧光检测法测定血浆总同型半胱氨酸水平。
2型糖尿病合并糖尿病视网膜病变组中MTHFR基因TT纯合型、CT杂合型及等位基因T的频率（分别为28.18%、41.82%、49.09%）显著高于无视网膜病变的2型糖尿病组（分别为18.37%、29.59%、33.16%）及对照组（分别为17.54%、28.07%、31.58%）。T等位基因的存在似乎与糖尿病视网膜病变的发生密切相关。优势比为1.94，95%置信区间为1.31 - 2.88。此外，TT或CT基因型患者的血浆同型半胱氨酸水平显著高于CC基因型患者。
MTHFR基因C677T突变与血浆同型半胱氨酸水平升高的易感性相关，可能被视为中国2型糖尿病患者糖尿病微血管病变（如DR）的遗传危险因素。
