In a new study appearing in the Aug. 7 issue of the New England Journal of Medicine, mutated versions of a gene called PALB2 can dramatically increase a woman’s risk of breast cancer. Women carrying the PALB2 mutation have a one-in-three probability of developing breast cancer by the age of 70.
The investigators found that the risk is even higher -reaching up to about six in 10- for women with a family history of breast cancer. Those odds place PALB2 just behind the BRCA1 and BRCA2 genes as a top genetic risk factor for breast cancer.
PALB tied to major breast cancer risk
For breast cancer, both BRCA genes have became the predominant biomarkers to evaluate a woman’s risk. According to the U.S. National Cancer Institute, Women who carry a mutated form of either of the BRCA genes have a 45% to 65% risk of breast cancer by age 70.
This new study provides the first solid evidence regarding the breast cancer risk associated with PALB2. Knowing this knowledge, women with a PALB2 mutation can talk with their doctor about whether they should undergo a surgery to reduce their breast cancer risk.
BRCA1, BRCA2 and PALB2 all play a significant role in the repair of damaged DNA. From the perspective of mechanism, PALB2 interacts with BRCA2, and acts as a kind of a bridge between BRCA1 and BRCA2. Mutation of any of the genes impairs the body’s ability to fix broken DNA, which can lead to cancer.
Breast-Cancer Risk in Families with Mutations in PALB2. N Engl J Med 2014; 371:497-506