摘要
建立蛋白截短检测技术,分析家族性腺瘤样息肉病(FAP)发病相关基因APC基因的胚系突变,研究基因突变型与FAP疾病表型的关系。经临床诊断的22例FAP患者及43例散发性大肠癌患者,分别取外周静脉血和正常结肠粘膜组织,常规提取基因组DNA。应用蛋白截短检测技术,分段分析APC基因巨大的第15外显子,对检出截短蛋白的样本进行测序,以确定突变位点及突变性质。22例FAP患者中,5例患者存在APC基因第15外显子的胚系突变,均为碱基缺失造成的移码突变,导致截短蛋白的产生;43例散发性大肠癌患者中未检测到APC基因第15外显子的胚系突变。蛋白截短检测技术是一种高效的基因突变分析技术,适用于大片段基因(如APC基因第15外显子)截短型突变的检测,可作为FAP症状出现前的常规基因诊断技术的一项有效补充。
The protein truncation test was established for analyzing mutations in the adenomatous polyposis coil (APC) gene which plays an important role in familial adenomatous polyposis (FAP). The sites of APC mutations and the clinic features of FAP patients were examined to find the relationship between them. Genomic DNA, which was extracted from peripheral blood lymphocytes of 22 FAP patients and the normal colon tissues of 43 sporadic colorectal cancers,were examined for mutations in exon15 of the APC gene by using PCR-TNT T7 Quick Coupled Tanscription/Translation System. The subsequent sequencing was used to confirm the mutation sites. Germline mutations were found in 5 of 22 FAP patients. All of the five mutations showed base pair deletions and led to produce truncated protein. No truncating germline mutation was found in normal tissues of 43 sporadic colorectal cancers. The protein truncation test is a sensitive and accurate technique to detect truncated mutations especially in the large exons of APC gene. It can be used as an routine method for assisting the early diagnosis of the FAP patients.
基金
江苏省卫生厅重点研究项目(编号:H200207)
江苏省应用基础项目(编号:BJ98078)资助~~