关键词: 基因，p53;突变;胃肿瘤;聚合酶链式反应;银染色法;序列分析，DNA

    摘 要:目的 探讨p53基因突变与人类胃癌发生的关系. 方法 运用PCR、PCR-SSCP结合银染法对25例胃癌组织p53基因第4、第5～6和第7外显子进行突变检测;运用双脱氧链终止法对第7外显子阳性突变标本进行DNA测序. 结果 在25例胃癌组织中检出突变5例，突变率为20%;在第7外显子阳性突变标本中发现了18bp的大片段缺失. 结论 p53基因突变与人类胃癌的发生具有明显相关性，并且这种突变可能不仅仅局限于点突变，大片段缺失也是p53基因突变方式之一.

    A study on mutation of p53gene in human gastric cancer with methods of PCR┐SSCP and DNA se┐quencing

    XU Shan SHAN Xiang-Nian

    1 Department of Biology，Basic Medical School，Nanjing Medical University，Nanjing210029，Chi-na，

    2 Department of Biology，Faculty of Preclinical Medicine，Nanjing Railway Medical College，Nan-jing210009，China

    Keywords:genes，p53;mutation;stomach neoplasms;poly-merase chain reaction;silver staining;sequence analysis，DNA

    Abstract:AIM To investigate the relationship between the mutation of p53gene and human gastric cancer.METHODS Mutations in exon4～7of p53gene were examined in25cases of gastric cancer by PCR and PCR-SSCP-Silver stain-ing.In addition，Sanger method(dideoxy-mediated chain-termination method)of DNA sequencing was used to examine the exon7which was positive in p53mutation.RESULTS Mutations were found in5cases(20%) ......