Researchers Uncover New Findings About Mutations That Increase Breast Cancer Risk

The mechanisms of BRCA mutations are still largely unknown.

Decades after the discovery that BRCA1 mutations increase the risk of breast cancer, researchers in a new study published by Nature have uncovered the mechanism that allows the mutations to affect the risk of cancer.

The authors report that these findings may guide future drug discovery, while also helping determine women at a high risk of developing breast and ovarian cancers.

“There have been about 14,000 papers written about BRCA1, and you would think we already know everything about the gene, but we don’t,” said senior author Patrick Sung, DPhil.

The finding that BRCA1 could modify DNA repair and tumor suppression was the first confirmation that cancer risk could be inherited, according to the authors.

Previously, BRCA1/2 mutations were thought to account for 7% to 8% of breast and ovarian cancers, but the authors report that these figures are much higher. In some cases, the expression of BRCA1/2 is silenced, despite a lack of mutation, according to the study.

In the study, the authors found that the interaction between BRCA1 and BARD1 is necessary to recruit the genetic sequence that repairs breaks in DNA. These breaks may be caused by stress and environmental factors, including radiation exposure, according to the study.

Despite significant progress made with the development of novel therapies and early detection methods, many Americans die of breast and ovarian cancer each year. With a better understanding of the genetic risks associated with the cancers, physicians may be able to recommend preventive options and more targeted therapies for those diagnosed.

“Defining the mechanism of the BRCA-dependent DNA repair pathway will help scientists design drugs to kill cancer cells more efficiently,” Dr Sung said. “Understanding this mechanism will provide the predictive power for doctors trying to establish a patient’s personal risk of developing cancer.”