3 New Genetic Mutations Linked to Male Breast Cancer
Our genes determine everything about our bodies. They play a key role in our health and can determine our likelihood of developing diseases. Some genetic mutations significantly increase the risk of developing breast cancer. The most common mutations associated with breast cancer involve the BRCA1 and BRCA2 genes. About 10% of male breast cancers are caused by mutations in the BRCA2 gene. Other examples of mutations that increase the risk of male breast cancer include those found in PTEN, PALB2, CHEK2 and NBN genes.
In addition to these well-recognized gene mutations, other very minor changes to our DNA code (known as single-nucleotide polymorphisms, or SNPs) also influence our risk of developing cancer. Unfortunately, these types of changes in our genetic code are much more common than BRCA gene mutations.
Although most genetic research associated with breast cancer risk is derived from studies in women, newly published findings bring insight on the genetic risks of developing breast cancer in men. A UK study, published in the Journal of the National Cancer Institute looked at the genotypes of 1,380 men diagnosed with breast cancer.
Results revealed that 3 new SNPs were significantly associated with an increased risk of male breast cancer. One of these SNPs is located on chromosome 6 (rs9371545), and two are located on chromosome 11 (rs554219 and rs78540526). These SNPs increase the risk of developing breast cancer in men by about 47%, 45%, and 61% respectively. Consistent with the predominance of ER-positive tumors in men, genetic correlation was strongest between male breast cancer and ER-positive female breast cancer. Although these genetic mutations are also linked to an increased breast cancer risk in women, the 3 new SNP variants have a greater impact on men.
Improved Decision-Making
While there is still a lot of research still needed, these findings can aid in the development of better risk assessment for men. For those choosing to undergo genetic testing, test results can help quantify individual risk and help guide treatment decision-making around risk-reducing options.
“This study, which shows more of a similarity between the genetic causes of the disease in men and women than previously thought, is a major step forward,” shared Dr Simon Vincent, director of research services at Breast Cancer Now. “Our knowledge of breast cancer in men is limited, because male breast cancer is rare which makes it difficult to collect enough tissue or blood samples to research and understand the disease. We now look forward to further research into the shared genetic causes of male breast cancer which could lead to developing risk reducing treatments and interventions to help prevent more cases among those at increased risk in the future.”
