同型半胱氨酸水平、MTHFR基因突变与原发性高血压的病例对照研究

目的:探讨升高的同型半胱氨酸水平、MTHFR基因突变与原发性高血压的关系.方法:从上海一个社区中随机选取127例35～75岁的原发性高血压病人和170例正常血压者.采用聚合酶链反应-限制性片段长度多态性分析MTHFR基因多态性.使用高效液相色谱结合电化学方法检测血清中同型半胱氨酸总浓度,使用放射免疫法同时测定血清中叶酸和B12浓度.结果:调整年龄和性别后,病例和对照组同型半胱氨酸水平分别为10.56 μmol /L 和 10.34 μmol/L,差异无显著性 (P=0.63).在未服降压药的对象中同型半胱氨酸浓度与收缩压和舒张压亦无关联.该人群MTHFR不耐热性基因突变频率为13.1%,突变等位基因频率为38.7%.病例组与对照组基因型分布和突变等位基因频率无显著性差异.然而,病例组叶酸和B12浓度高于对照组.结论:本研究未发现升高的同型半胱氨酸水平、MTHFR基因突变是原发性高血压的独立危险因素.高血压病人较高的叶酸和B12水平可能降低了同型半胱氨酸的危险性.

Elevated serum homocysteine,MTHFR gene mutation and essential hypertension in Chinese

Objective: To examine the relationship between elevated homocyst eine levels,mut ation of the MTHFR 677 C to T and essential hypertension in a Chinese population,a commu nity-based case-control study was conducted.Methods: 127 essential hypertension patients of age 35 to 75 were ra ndomly selected from a community. 170 control subjects with blood pressure <140/90 mmHg were selected from the same community. MTHFR genotypes were identified by PCR and restriction fragm ent length polymorphism analysis with Hinf I digestion. Serum homocysteine was dete rmined using HPLC. Folate and vitamin B12 were measured by radioimmunoassay.Results:After adjusting for age and sex,the mean homocysteine leve l was 10.56 μmol/L for hypertensive patients and 10.34 μmol/L for controls (P=0.63). No associatio n between either SBP or DBP and Hcy concentration was found in subjects without anti-hype rtensive medications. The prevalence of homozygousity for thermolabile MTHFR variant for this population was 13.1%,and the mutant allele frequency was 38.7%. There was no significant difference on genotype distributions and the mutant allele frequency for two groups studied. However,the concentrations of folate and B12 for the hyper tensive subjects were generally higher than the controls. Conclusions:The present study didn't find that elevated Hcy levels or MTHFR mutation are independent risk factors for essential hypertension. The higher folate and B 12 in the hypertensive subjects might contribute to lower the risk of homocysteine.