BRCA2 Gene Mutations Detection In Patients With Sporadic Breast Cancer

Objective:To detect the mutation sites of BRCA2 gene in 100 patients with breast cancer and to study the relationship between BRCA2 gene mutation and breast cancer.Methods:Breast cancer tissues of 100 patients were studied,and breast tissues of 30 cases of patients without cancer were randomly selected as controls.Each tissue sample was ground thoroughly in mortar with pestle.DNA was extracted by the phenol-chloroform method.To determine the concentration and purity of the DNA solution,the absorbance of UV light is measured in a spectrophotometer.Fragments of exon1,exon2,exon3,exon4,exon 5,exon6,exon8,exon9,exon10,exon11,exon12,exon13,exon14,exon15,exon16,exon17,exon18,exon19,exon20,exon21,exon22,exon23,exon24,exon25,exon26and exon27 in the BRCA2 gene were amplified by PCR.There're 28 primers in all for PCR.Single-strand conformation polymorphism analysis(SSCP)was used for the BRCA2 gene mutational screening,and alterations were confirmed by DNA sequencing.Result:.No mutation was identified in the controls.A total of 2 single nucleotide changes in BRCA2 were detected in the 100 cases of breast cancer patients, including 1 base change(G→C)in BRCA2 gene sequence 61917 site (IVS22+4),1 base change(A→G)in 31828 site.The 2 base change were all in intron domain.Conclusions:The two BRCA2 gene intron mutations were not similar with foreign or domestic reports.The 61917 site(IVS22+4)intron mutation which lies in the splicing domain maybe adverse to the transcription of exon.The BRCA2 gene mutation in sporadic breast cancer of our country should be studied deeply.