论文部分内容阅读
目的 蛋氨酸合酶 (MS)是同型半胱氨酸代谢关键酶 ,旨在了解其与先天性心脏病(CHD)发生的关系。方法 选择 186名多种类型CHD患者 (0～ 31岁 ,性别比约为 1∶1)作为病例组 ,以同地区且年龄、性别匹配的 10 3名正常人作为对照 ,进行MS基因A2 75 6G位点多态性分析 (PCR RFLP法 )及血清叶酸、维生素B12 (VB12 )水平的测定 (放射免疫法 )。结果 显示本研究人群中存在MS基因A2 75 6G位点杂合突变 (+ - ) ,但未检出纯合突变 (+ +)基因型 ;其中对照组 (+ - )基因型和 (+)等位基因的频率分别为 10 7%和 5 3% ,低于报道的白种人及日本人变异频率 ;病例组 (+ - )基因型和 (+)等位基因的频率为 9 1%和 4 6 % ,与对照组相比其基因型构成差异无显著性 ;(+ - )基因型罹患CHD的比值比 (OR)为 0 84 (95 %可信区间 ,0 35～ 2 0 1) ;不同类型CHD与对照组的基因型构成亦无明显差异 ;此外病例组血清VB12 水平低于对照组 (336 6 6pmol L和 4 6 5 72pmol L) ,但无统计学意义 (P >0 0 5 ) ;两组的叶酸水平无明显差异 ;病例组不同基因型叶酸、VB12 水平差异亦无显著性。结论 MS基因A2 75 6G位点变异与CHD及血清叶酸、VB12 水平无明显关联 ,还有待进一步研究。
The purpose of methionine synthase (MS) is a key enzyme in homocysteine metabolism, to understand its relationship with the occurrence of congenital heart disease (CHD). Methods One hundred and sixty-eight patients with multiple types of CHD (0-31 years old, sex ratio of about 1: 1) were selected as the case group and 10 3 normal subjects of the same age and sex matched with the control group. (PCR RFLP) and serum folic acid, vitamin B12 (VB12) levels (radioimmunoassay). The results showed that there was heterozygous mutation (+ -) of A2 75 6G site in MS population but no homozygous mutation (+ +) genotype was detected in the population. The genotype and (+) The frequencies of the alleles were 10 7% and 53%, respectively, lower than those reported for Caucasian and Japanese; the frequency of genotypes and (+) alleles in the case group was 91% and 4% 6%. There was no significant difference in the genotypes between the control group and the control group (odds ratio [OR] 0 84 (95% confidence interval, 0 35 ~ 2 0 1) There was also no significant difference in the genotype between CHD and control group. In addition, serum VB12 level was lower in the case group than in the control group (336 6 6 pmol L and 465 72 pmol L), but not statistically significant (P 0 05). There was no significant difference in folic acid levels between the two groups. There was no significant difference in the folic acid and VB12 levels between different genotypes in the case group. Conclusion There is no significant correlation between the mutation of A2 75 6G of MS gene and the serum levels of CHD, folic acid and VB12, which remains to be further studied.