摘要:目的: 检测大肠癌组织中Kras基因的突变情况以指导临床治疗。 方法 :通过提取15例大肠癌石蜡组织中的DNA并进行PCR扩增,之后采用国际金标准方法直接测序法进行检测获得突变信息。 结果 :15例大肠癌石蜡组织样本中Kras有4例发生突变,突变率为266%。值得注意的是发现一个新的突变位点密码子42,并且与密码子12突变共存。 结论 :密码子42的突变进一步证明Kras突变不仅局限于密码子12,13,61,还有与密码子12共存的42位突变。Abstract: Objective: To detect the mutation status of Kras gene in colorectal cancers and to assist the clinical treatments Methods : DNA was extracted from fifteen formalinfixed, paraffinembedded tumor samples of colorectal cancers, and then the fragments containing codons 12,13 and codon 61 were amplified by PCR The sequences were indentified by direct sequencing which is gold standard for the detection of mutation Results : In the 15 samples of colorectal cancer patients, 4 mutations were observed, with 2 in codon 12 and 2 in codon 13 Suprisingly, a novel point mutation at codon 42 of Kras was found, and coexisted with mutation in codon 12 Conclusion : Except for codons 12,13,61 mutation, Kras has other mutation at codon 42 with coexisted with codon 12 point mutation