BRCA Gene and Genetic Testing
There are several factors that are associated with an increased risk for breast cancer. One of the most significant variables is genetics, as about 5 to 10 percent of breast cancers may be hereditary. Perhaps you have someone in your family who has traveled this difficult journey, and you are worried about your risk of being diagnosed with breast cancer. National Breast Cancer Awareness Month is a great time to learn the facts about the BRCA gene and whether genetic testing is right for you.
What is the BRCA gene and how is it related to breast cancer?
Genes provide instructions for cell functioning. Oncogenes speed up cell division, and tumor suppressor genes slow it down or cause normal cell death. The BRCA genes are categorized as tumor suppressor genes. Breast cancer gene one (BRCA1) and breast cancer gene two (BRCA2) are genetic "mutations, and are the most common cause of inherited breast cancer. The presence of a BRCA gene can “turn off” genes that would otherwise work to suppress tumors, causing normal cells to become cancerous, and placing individuals who inherit them at increased risk. Of the two, BRCA1 mutations carry the most risk for developing breast cancer. The average range of acquiring breast cancer from a BRCA1 mutation is 55 to 65 percent. However, BRCA1 mutations can increase risk as much as 80 percent. The risk of developing breast cancer that is caused by a BRCA2 mutation is lower, around 45 percent.
Who should be concerned about genetic risk?
To put all of this into context, an average woman in the U.S. has about a 12 percent risk (1 in 8 women) of developing breast cancer at some time in her life. Although breast cancer is much less prevalent in men, about 1 in 1,000 men may develop it in their lifetime. It does occur, and men with an abnormal BRCA2 gene are about 80 times more likely to develop breast cancer by the time they’re 80 years old.
Having a BCRA gene mutation does not equate to having breast cancer, as a variety of factors affect your risk level. However, you should be aware that you are more likely to have an abnormal BRCA gene if any of the following applies to you:
- A history of breast cancer before age 50 in any blood relatives
- A family history of both breast and ovarian cancers, especially in the same person
- A history of bilateral breast cancer for any women in your family
- Eastern European heritage
- A history of male breast cancer in your family
If you think you are at increased risk, what is next?
If you do think you are at increased risk, the next conversation you should have is with your primary care provider. A few tips to prepare you for the conversation include:
- Organize the results of your research and provide your physician with the details of cancer in your family.
- Create a simple family tree of who had what type of cancer to provide a snapshot of your history.
- Focus on the risk factors you see that are associated with potential BRCA gene mutations.
- Ask about genetic testing, which can help identify if you actually do have an inherited BRCA gene abnormality.
- Create a plan together for prevention and early detection.
If you would like to further explore your risk for developing breast cancer, the Centers for Disease Control and Prevention (CDC) has developed the Know: BRCA online tool. This is a resource to help assess your hereditary risks. Based on the information you provide about your personal and family history of cancer, it can tell you whether or not you have an above-average chance of having a BRCA gene mutation. The video below demonstrates where to find the assessment, as well as more information about BCRA genes.
In addition to talking with your primary care provider, you will want to discuss your concerns with your family, especially with those who may be at higher risk. By knowing the facts about the BRCA gene, mutations, and genetic testing, you can increase awareness and lay a foundation for breast cancer prevention.