A Novel Mutation-BRCA1 Associated Hereditary Haplotype of Intragenic Markers of BRCA1 Gene in a Family with History of Breast Cancer

Background: Breast cancer is the most common cancer diagnosed among women, Tumor suppressor genes such as BRCA1 involved in cell cycle control and repairing of DNA damage. BRCA1 is a risk factor gene that alteration in its protein cause in susceptibility to breast or ovarian cancer. Short tandem repeat (STR) polymorphism is linked to some disease. Objective: The aim of this study was screening a new mutation in patients with familial breast cancer. Materials and Methods: In this study, 200 women with breast cancer were participated. Among the patients, 40 women suffer from familial breast cancer. After DNA extraction from peripheral blood samples, Exons 16 to 23 of BRCA1 gene directly analyzed in SSCP gel electrophoresis followed by direct sequencing. Results: After direct sequencing, a new mutation was detected in intron 17 of BRCA1 gene. Three patients of one family have a germ line intronic mutation in the BRCA1 gene (IVS17-27delA). Also, this mutation in this family is linked to a haplotype of intragenic short tandem repeat (STR) in the BRCA1 gene. Conclusion: By Screening of gene mutations can be found association of mutation and incidence of disease. Also, studying the mutation in families and finding specific hereditary patterns in that family can be effective in prognosis of disease in other family members.