Media release

From: Springer Nature

Genetics: Genetic variants for breast cancer risk in women of African ancestry identified

Genetic variants that may contribute to the risk of developing breast cancer among women of African ancestry are reported in a paper published in Nature Genetics.

Breast cancer is the most commonly diagnosed cancer in many parts of the world, but incidence and subtype distributions appear to vary by genetic ancestry. Women of African ancestry are more likely to develop the disease at an earlier age than women of European ancestry, and are more likely to have an aggressive form called triple-negative breast cancer (TNBC). Despite this, most breast cancer genetic research has focused on populations of European ancestry.

Wei Zheng and colleagues conducted a genome-wide association study of breast cancer in women of African ancestry. Using data from 18,034 cases of breast cancer and 22,104 controls from women of African ancestry (85.3% from the USA and 14.7% from the African continent and Barbados) they focused on small regions, or ‘loci’, of the genome that vary between individuals. The authors identified genetic variants at 12 loci associated with breast cancer risk in women of African ancestry at the genome-wide significant level. Of them, variants in three loci were associated with risk of TNBC. Approximately 8% of African-ancestry women carry all six risk variants in these loci, and these women are 4.2 times more likely to be diagnosed with TNBC than those who carry none or only one of the variants.

The authors suggest that their findings could be used to improve risk prediction in this population and provide the basis for more tailored detection and prevention strategies.