Background & Objectives : Breast cancer is among the most frequent disorders among the world. BRCA1 gene was known as a tumor suppressor gene which its loss could be resulted in various destructions in genome. Therefore, changes occurred in its expression level could lead to increasing the effects of oncogene activity on breast cells.

  Methods : RT-PCR and Q-RT-PCR were used for detecting BRCA1 expression status among 27 primary affected breast cancer patients. The association between its expression status and histopathologic data had been evaluated by statistical assays.

  Results: Eighty-five percent of patients showed BRCA1 expression and this expression as well as its quantity had significant associations with tumor grade. It was found that tumors with low levels of BRCA1 expression tend to have higher grades.

  Conclusion : BRCA1 has an important role in suppressing breast tumorogenesis. Corresponding to some of the previous reports, our findings revealed the role of decreasing in BRCA1 expression level as one of the factors which allows tumors to progress.