BREAST CANCER: SCIENTISTS DISCOVER TWO NEW GENETIC RISK FACTORS

Thanks to an international collaboration between cancer research centers and scientists, breast cancer genetics and the understanding of risk factors have revealed two new genetic sites that impose a higher risk for the women who have them.

The multicenter study published in the journal, Human Molecular Genetics, describes two new variants, rs10816625 and rs13294895, on a region of chromosome 9. These newly discovered factors specifically increase risk for estrogen receptor positive breast cancer, the most common form. The study and the conclusions made from it show a need to improve the screening of women to identify those with high risk of developing breast cancer in their lifetime. The early screening and identification of women at risk could potentially lead to earlier intervention and prevention of breast cancer.

The study to specifically map chromosome 9 was undertaken by over 130 institutions from around the world and included 43,160 breast cancer cases and 42,600 controls cases of women with European ancestry, and 5,795 breast cancer cases and 6,624 control cases of Asian ancestry.

The lead researcher Dr. Nick Orr, from The Institute of Cancer Research London, commented that, “The variants we identified are specifically associated with the most common, estrogen receptor positive, form of breast cancer. The more genetic risk factors for breast cancer we discover, of which there are currently over 80, the more accurately we will be able to predict who is at risk of getting the disease. Ultimately, this will be vital for designing preventative strategies against breast cancer.”

The results of the study concluded that variant rs10816625 increased risk of developing breast cancer by 12% and specifically, estrogen receptor positive breast cancer by 14%, while variant rs13294865 increased risk by 9% and 11%, respectively. The study did not show direct correlation of these variants with estrogen receptor negative breast cancer. By ancestry, rs10816625 was associated with risk for both European and Asian women, and rs13294895 was associated with increased risk primarily in European women.

Genetic screening does not detect cancer, but reveals a predisposition for developing breast cancer. Women at high risk, particularly those with a family history of cancer may be referred for genetic testing or other screening procedures.