结直肠腺瘤性息肉APC基因突变的DNA测序分析

Analyses of APC Gene Mutations in Colorectal Adenomatous Polyps by DNA Sequencing

目的探索广西地区结直肠腺瘤性息肉组织中腺瘤性息肉病(Adenomatous?polyposiscoli,APC)基因的突变类型。方法应用聚合酶链反应(Polymerasechainreaction,PCR)方法扩增APC基因的相应片段,以制备DNA测序的模板,然后用DNA自动测序仪进行测序。结果共检出5种APC基因突变类型,即,密码子1322(GGA>TAA)、密码子1379(GAG>TAG)、密码子1396(-TT)、密码子1414(-G)和密码子1429(CAA>TAA)。结论这5种突变中有3种为无义突变,其余2种为移码突变,从而使终止密码提前出现,APC蛋白的生物合成提前终止,由此产生无功能的截短APC蛋白。

Objective：To identify APC gene mutations in colorectal adenomatous polyps in Guangxi. Methods：DNA sequencing template was prepared by using PCR. DNA sequencing was performed on an automatic sequencer （ABI PRISM 377-96） with the kit of Big Dye terminator v2.0. Results： 5 types of APC gene mutations were identified, namely, codon1322 （ GGA〉TAA ） ,codon1379 （ GAA〉TAA ） ,codon1396 （- TT）,codon1414（-G）and codon1429（CAA〉TAA）. Conclusion：These 5 mutations include 3 nonsense mutations and 2 frameshift mutations. All of them would result in the premature stop of APC protein synthesis and generate truncated APC protein.