A common set of genetic mutations has been linked to multiple types of cancer and now the women carrying these gene variants can add breast cancer to that list.
When women carry the gene mutations, a condition known as Lynch syndrome, they also carry a significantly higher risk of colorectal cancer and uterine cancer, as well as an increased risk of cancer in their ovaries, stomachs, livers, small intestines, skin and brain, among other locations. After looking into the DNA of breast cancer patients, researchers now say that a significant portion of those women carry the troublesome genes.
Lynch syndrome does not display other symptoms, but the increased risk of cancer coupled with the pattern the scientists observed has them calling for women to get tested for the genes if they have a family history of breast cancer. Their study in the journal Genetics in Medicine reported that of the handful of genetic mutations linked to Lynch syndrome, the mutations to genes called MSH6 and PMS2 were associated with a heightened risk — up to two or three times that of the general population.
“Individuals reporting a personal or family history of colorectal and uterine cancers are often tested for these genes,” journal publisher Springer explained. “However, genetic tests are generally not included when breast cancer is the predominant cancer in a family.”
The scientists calculated the breast cancer risk by digging into the genetic information of thousands of women and reviewing the cancer histories of those who were found to carry Lynch syndrome genes. Out of those more than 400 gene carriers, about a quarter had a history of breast cancer.
Roughly one in every 370 people has Lynch syndrome.
“Our data demonstrate that … MSH6 and PMS2 are associated with an increased risk for breast cancer and should be considered when ordering genetic testing for individuals who have a personal and/or family history of breast cancer,” lead author Maegan Roberts said in the journal statement. “Given that Lynch syndrome is not rare in the general population, this finding has the potential to impact tens of thousands of people in the U.S.”