血管紧张素原基因M235T基因多态性与胎儿生长受限关系的探讨

The study of relationship between polymorphism of angiotensinogen gene M235T and fetal growth restriction

目的研究血管紧张素原基因(AGT)M235T基因变异与中国汉族孕妇胎儿生长受限(FGR)的关系。方法应用PCR及PCR产物直接测序方法对100例FGR孕妇(研究组)及100例非FGR孕妇(对照组)AGT基因第二外显子704处基因进行检测。结果发现AGT基因第二外显子704处存在核苷酸T被C替代的变异,使235位密码子编码产物蛋氨酸(Met235,M)被苏氨酸(Thr235,T)所替代。AGT基因MM、MT、TT基因频率研究组分别为0.04、0.31、0.65,对照组为0.1、0.45、0.45,两组相比差异有统计学意义(χ2=8.787,P<0.05)。研究组TT纯合子明显高于对照组。Met235、Thr235等位基因频率研究组分别为0.195、0.805,对照组为0.325,0.675,两组相比差异有统计学意义(χ2=8.784,P<0.01)。研究组Thr235等位基因频率明显高于对照组。结论中国汉族孕妇中AGT基因M235T变异可能为FGR的遗传高危因素。

Objective： To explore the relationship between molecular variant of M235T of angiotensinogen （AGT） gene and fetal growth restriction （FGR） in the Chinese Han pregnant women. Methods： A case -control study was carried out using 100 cases pregnant women with FGR as study group and 100 cases pregnant women with non - FGR as control group. Polymerase chain reaction （PCR） and the direct sequencing of PCR products were used to scan the molecular variant at locus 704 of the second extron of AGT gene. Results ： There was a nucleotide substitution of T to C at 704 locus of second extron of AGT gene, made threonine （ Thr235, T） instead of methionine （ Met235, M） at position 235. The distribution of genotypes MM, MT, TT showed significant difference between the study group and the control group （0. 04, 0. 31,0. 65 vs 0. 1, 0. 45, 0. 45; X2 =8. 787, P〈0. 05）. The TT homozygous in the study group was significantly higher than that of the control group. There was significant difference of Met235 and Thr235 allele X2 frequency between the two groups （0. 195, 0. 805 vs 0. 325, 0. 675 ; = 8. 784, P 〈 0. 01 ）. Thr235 allele frequency in the study group was significantly higher than that in the control group. Conclusions： The results suggest that the molecular variant of M235T of AGT gene might play an important role in the occurrence of fetal growth restriction in the Chinese Han pregnant women.