Study Reveals Breast Cancer Genes Unique to Black Women in South Africa.

A groundbreaking study explores breast cancer genes in Black South African women for the first time.

New research has discovered genetic variants linked to breast cancer in Black South African women.

Published in Nature Communications, the study found two genetic variants linked to breast cancer, shedding light on the disease’s genetic origins in African populations. This marks the first genome-wide association study (GWAS) on breast cancer conducted among African women living in Africa.

In the study, researchers from the Sydney Brenner Institute for Molecular Bioscience (SBIMB) identified consistent genetic patterns linked to breast cancer in Black South African women. They discovered genetic signals near the RAB27A gene, part of the RAS oncogene family, and the USP22 gene, which is highly active in breast cancer cells and associated with worse outcomes.

“These genes have never before been linked to the disease, marking a significant step forward in understanding breast cancer risk and biology in women of African ancestry,” said Dr. Mahtaab Hayat, the lead author of the study, as reported by Medical Express.

Until recently, breast cancer genetics research primarily focused on European and Asian populations, with little attention given to those of African ancestry, particularly African American women of West African descent. A DNA-based tool called the polygenic risk score (PRS), used to estimate lifetime cancer risk, was found ineffective in distinguishing between South African women with and without breast cancer.

“This is because most PRSs were developed using European populations, and their lack of accuracy in African populations underscores the urgent need for ancestry-specific tools in cancer risk prediction,” said Dr. Jean-Tristan Brandenburg, also a lead author at SBIMB.

Breast cancer is the second most common cancer in South Africa and the leading cancer among women globally, with genetics contributing to about 30% of cases. African populations, which have the greatest genetic diversity in the world, are still largely underrepresented in genomic research, hindering global understanding of disease risk and the development of effective tools and treatments.