同型半胱氨酸代谢相关酶基因多态性与心肌梗死关系的研究

目的研究同型半胱氨酸代谢相关酶亚甲基四氢叶酸还原酶(MTHFR)、胱硫醚-β-合成酶(CBS)及蛋氨酸合成酶(MS)基因多态性与心肌梗死(MI)相关性。方法应用聚合酶链反应-限制性内切酶片段长度多态性(PCR-RFLP)和聚合酶链反应(PCR)产物直接电泳技术,检测121例MI患者(患者组)和500例健康人(正常对照组)的MTHFR C677T、CBS 844 ins68和MS A2756G基因多态性。结果MTHFR C677T基因型分别为:CC野生型、CT杂合型、TT突变型。其在患者组分布频率分别为14.0%、46.3%、39.7%,T等位基因频率为62.85%,C等位基因频率为37.15%;正常对照组中为35.6%、44.0%2、0.4%,T等位基因频率为42.4%,C等位基因频率为57.6%。两组间各基因频率及等位基因频率比较差异均具有统计学意义(P<0.05)。而CBS 844ins 68和MSA2756G的基因型频率分布,两组间差异均无统计学意义(P>0.05)。结论MTHFR基因TT基因型,T等位基因与MI具有相关性;而CBS 844 ins68及MS A2756G基因多态性可能与MI发生无直接相关性。

Relationship between the genetic polymorphisms of homocysteine metabolic related enzymes and myocardial infarction

Objective To observe the relationship between the genetic polymorphisms of homocysteine metabolic related enzymes methylenetetrahydrofolate reductase(MTHFR),cystathionineβ-synthase(CBS) 844ins 68 and methionine synthase(MS) and myocardial infarction(MI).Methods 121 myocardial infarction patients and 500 normal controls were recruited in the study,their polymorphisms of MTHFR,CBS and MS genes were analyzed by means of polymerase chain reaction and restriction fragment length polymorphism(PCR-RFLP)or polymerase chain reaction(PCR).Results There were three kinds of genotype in MTHFR: CC(homozygous normal),CT(heterozygous)and TT(homozygous mutation).Among three genotype of the patients,CC was accounted for 14.0%,CT for 46.3%,TT for 39.7%,while the frequency among control subjects were 35.6%,44.0%,20.4 %,respectively.The frequency of T alleles was significantly higher in patients than that in normal controls(62.85% and 42.4%,respectively). There was a difference Statistically in the frequencies of genotype and alleles between two groups(P<0.05).But for the CBS 844 ins68 and MS A2756G, there was no difference statistically between two groups(P>0.05).Conclusions There is an association between TT genotype and T alleles of MTHFR gene,neither the genetic polymorphisms of CBS 844 ins68 nor MS A2756G,and myocardial infarction.