A Study On Apc Gene E15 Mutation In Two Familial Adenomatous Polyposis Pedigree

Objective: The mainly character of Familial adenomatous polyposis (FAP) is morethan 100 adenoma polypi in colorectal duct. Some patients can intercurrent tumors out of large intestine such as desmoids, ploypi in upper alimentary canal, thyroid cancers and periampullary tumors. The malignant potential of FAP is completed without therapy. The Hereditary FAP exhibits delayed dominance of autosome. incidence of the disease about the patients is 1/2. It's important to reduce the rate of disease through genetic diagnosis, screen out the gene background of the patient's kinfolks. So we can found the patients of pre-symptom and carrier and as early as possible to treatment.By far, we considered the mutation of APC gene is an early event of colorectal duct tumorgenesis. APC gene is a kind of tumor suppressor gene, can mutate in germline cells and somatic cells. The mutation in germline cells is the important genetic foundation of the FAP. The mutation of APC gene include deletion , insertion, point mutation, duplication and terminal code mutation. More than 60percent of the mutation about APC gene occurred in the 15^th exon.In our country there are few reports of the mutation in germline cells in the APC gene, so through deeply and broadly study on the APC gene, we can found the mechanism and build the effective monitor system of the disease. It's great significance to reduce the incidence of the disease to death. In this research we screened the 15^th exon mutation in APC gene of the two FAP pedigrees in order to give some information on FAP genetic diagnosis and predict livability by evaluate the mutation in the gene.methods: from October to December 2006, we investigated two FAP pedigreescome from Henan province, the sample divided into two groups, one is 9 patients and 24 kinfolks as test group, the other is one sporadic FAP patient and 2 random normal as control.the members of two group are all Han folk, and gender and age are randpm. The specimen are anti-cruored by 2% EDTA-K2, purification the genome DNA use the hydroxybenzene -chloroform method, use PCR-SSCP method to screen out the APC gene 15^th exon, the positive specimen be send to sequence.results: from the results of electrophoresis wo can draw a conclusion, two groupsspecimens are accord with the anticipation. the DNA sequence is also accord with the expected.Conclusions(1) The APC gene 15^th exon of the two pedigrees have no mutation.(2) The genetic diagnosis of APC gene can't to be the exclusive criterion to determinate the FAP.(3) In this study, whether the FAP patients have mutations except the 15^th is not involved.