汉族人群血管紧张素原基因的新单核苷酸多态性位点

应用改进的PCR－SSCP技术、多种聚丙烯酰胺凝胶电泳和PCR产物直接测序等方法，分析人的血管紧张素原（AGT）基因启动子区5远侧端的单核苷酸多态性（SNP）。在非变性胶上，发现不同样品的PCR产物（双链DNA分子）电泳迁移率不同；而在变性胶上，对应的单链DNA分子电泳迁移率相同；PCR产物直接测序的结果表明，在同一PCR扩增片段中同时存在两个SNPs位点（G－1074T，A－1179G）；通过476个不同样品的实验结果，进一步证实两个SNPs位点处于完全的连锁不平衡关系。GenBank同源性比较结果显示：A－1179G为中国汉族人群所特有。

A novel SNP of human angiotensinogen gene from Chinese Han population

Polymerase Chain Reaction Single Strand Conformation Polymorphism (PCR SSCP) , Polyacrylamide Gel Electrophoresis(PAGE) and direct sequence analysis of PCR products were applied to screen Single Nucleotide Polymorphisms (SNPs) in 5 'distal region of human angiotensinogen(AGT) gene promoter. Results demonstrated that under nondenaturing conditions, electrophoretic mobility shifts of PCR products(double strand DNA)varied among different samples,but corresponding single stranded DNA of PCR products showed the same electrophoretic mobility under denaturing conditions. Direct sequencing indicated that two SNPs were existed in the same PCR amplified fragment(G 1074T, A 1179G). Genotyping data of 476 samples confirmed that these two SNPs were in complete linkage disequilibrium with each other, meaning that multiple existence of SNPs might lead to electrophoretic mobility shifts of double strand DNA fragments. Comparisons of nucleotide sequences using Blast program of Genbank showed that A 1179G was a novel,special SNP from Chinese Han population.