Association Between BRCA1 Gene Polymorphism and Breast Cancer Risk in Women at the University College Hospital, Ibadan

Breast cancer is the most common malignancy among Nigerian women, with incidence rates rising steadily over the past decade. Germline mutations in the BRCA1 gene confer substantially elevated lifetime risk of breast and ovarian cancers. While BRCA1 studies have been conducted extensively in European populations, African-specific variant data remain underrepresented globally. This preliminary case-control study investigated the association between selected BRCA1 polymorphisms and breast cancer risk in women attending the oncology unit of the University College Hospital (UCH), Ibadan, Oyo State. Forty histologically confirmed breast cancer cases and 40 age-matched controls were enrolled. Blood samples were collected for DNA extraction, and PCR-RFLP was used to genotype the BRCA1 c.181T>G polymorphism. Clinical staging, family history of breast cancer, and reproductive history were documented. While the sample size was limited in this preliminary investigation, a trend toward increased frequency of the variant allele in cases compared to controls was observed, consistent with published data from other African cohorts. These findings advocate for larger multi-centre BRCA1 screening studies in South West Nigeria. Keywords: BRCA1, breast cancer, polymorphism, PCR-RFLP, University College Hospital Ibadan