胃腺癌p53基因第5、7外显子突变的研究

MUTATIONS IN EXONS 5,7 OF p53 GENE IN GASTRIC ADENOCARCINOMAS

采用聚合酶链式反应－单链构型多态（ＰＣＲ－ＳＳＣＰ）技术结合ＰＣＲ产物直接测序方法初步分析了２３例原发性胃癌ｐ５３基因第５、７外显子的突变。经ＳＳＣＰ检测发现第５外显子无一例异常泳动变位，而第７外显子发现２例阳性结果（突变率８．７％）．经测序证实一切发生了剪切位点突变，另一例突变为静息突变。

p53 gene is the most frequently mutated tumor suppressor gene which mutated roughly in 50% of all tumors,The mutations of exons 5 and 7 of p53 gene in 23 patients with primary gastric cancer were studied using the method of PCR-SSCP and PCR products direct sequencing.There was no positive result in exons 5 in all the 23 patients,but a single-strand conformational polymorphism band shift in exons 7 was found in two cases.The results of DNA sequencing indicated that one is a spliting site muta tion,(codons 261)AGgtca…intron7…tagT──ATgtca…intron7…tagT;the other is a silent mutation(codon8257);CTG→TTG.