Mohaddeseh Khalilian - PhD., Department of Microbiology, Faculty of Biological Sciences, Shahid Beheshti University, Tehran, Iran.
Seyed Masoud Hosseini - DVM & PhD., Department of Microbiology, Faculty of Biological Sciences, Shahid Beheshti University, Tehran, Iran.
Omid Madadgar - DVM & PhD., Department of Microbiology & Molecular Genetics, Biomedical Physical Sciences, Michigan State University, USA.

Background: Breast cancer is the most common invasive cancer among women in world. Breast cancer most often begins with cells in the milk-producing ducts (invasive ductal carcinoma). Bovine leukemia virus (BLV) is an oncogenic retrovirus that causes B-cell leucosis in 1–5% of infected cattle. The aim of this research was evaluation of a relationship between BLV and breast cancer in Iranian women. Materials and Methods: A total 200 breast cancer-suspected tissue samples were collected during July 2017- October 2018 from women referring to hospitals of Qom province, Iran. tax gene of BLV was detected by Nested PCR technique. Results: tax gene of BLV were detected in 30% (60/200) of breast cancer-suspected tissue samples. It is considerable that BLV DNA identified even after chemotherapy in some breast cancer samples. Also, Age rang in women with breast cancer was 35-73 years. Conclusion: This study was showed a relationship between human and BLV infection. It can be one of risk factors for developing breast cancer.

Bovine leukemia virus, Breast cancer, Nested PCR.