Your genetics influence everything — from your appearance to your mental capabilities to even your natural inclinations for certain talents. They also play a role in your chances of developing some diseases. 

Genetic testing helps determine if a condition runs in your family before you experience any symptoms. With a simple blood or saliva sample, it allows you and your healthcare provider to keep a closer eye on your health, including reducing other risks and staying up-to-date with screenings. In some cases, genetic testing can save lives. 

Breast cancer genetic testing focuses on changes in the BRCA genes, which have been associated with a risk of breast cancer and other cancers, like ovarian cancer, since the discovery of BRCA gene mutations in 1994. Today, it’s a part of many cancer care plans to identify breast cancer early (when it’s easier to treat) or prevent it completely. 

Here’s how genetic testing for breast cancer works and how it may fit into your life. 

An Overview of the BRCA1 and BRCA2 Gene Mutations

Your cells contain DNA, which is the genetic material of the cell. DNA contains the instructions (called genes) that tell cells how to function and how to behave. Changes in these genes — also known as mutations — can keep them from doing their job. 

The BRCA1 and BRCA2 genes are responsible for protecting you from developing certain cancers. If these genes contain a mutation, your risk of cancer is higher than the average person. 

Women who have a BRCA1 or BRCA2 gene mutation are more likely to develop cancers of the breast, ovaries, and pancreas. Men with the mutation are more likely to develop cancers of the breast, prostate, and pancreas. There may also be other cancers associated with these gene mutations. 

Gene changes are passed from parents to children. Any child of a parent who has a BRCA1 or BRCA2 gene mutation has a 1 in 2 chance of inheriting that mutation. 

Who Might Benefit from Genetic Testing for Breast Cancer? 

Genetic testing reveals a lot of information — all with a blood or saliva sample. Samples are sent for testing in a lab, where healthcare experts will look for mutations within the DNA.

Before getting tested, you’ll meet with a genetic counselor to do a risk assessment. This will help determine if you would benefit from genetic testing. The typical recommendation for genetic testing for breast cancer is for women who have a higher risk of inheriting the BRCA1 or BRCA2 gene mutation, such as those who have: 

• A family history of breast or ovarian cancer that is considered strong, such as one or more first- or second-degree relatives being diagnosed with breast cancer before the age of 50
• A family history of breast or ovarian cancer that is considered moderate, such as a first-degree relative being diagnosed with breast cancer after age 50, paired with Ashkenazi or Eastern European Jewish ancestry
• A personal history of fallopian tube, ovarian, or primary peritoneal cancer
• A confirmed BRCA or other inherited gene mutation in the family 

Breast cancer genetic testing may also be used for people who have already been diagnosed with cancer, as it can help dictate the best course of treatment. 

Using the Results from Breast Cancer Genetic Testing

The results of genetic testing can be confusing and may not always provide clear-cut next steps. That’s why genetic counselors play a crucial role in analyzing the results and determining how they fit into your care plan and that of your family members. 

 

A Positive Result 

If your genetic testing comes back with a positive BRCA1 or BRCA2 gene mutation, you have a mutation that may cause breast and ovarian cancer. Knowing this, you can take steps to reduce your risk of cancer or find it as early as possible, such as: 

• A mastectomy (surgery to remove the breasts)
• A salpingo-oophorectomy (surgery to remove the ovaries and fallopian tubes)
• Medications
• Annual screening with breast MRI and mammograms
• More frequent self and clinical breast exams
• Reducing other risk factors, such as maintaining a healthy weight 

Your genetic counselor may also recommend other family members undergo genetic testing. 

A Negative Result

A result that comes back negative means the test didn’t detect a BRCA1 or BRCA2 mutation. This might mean a few different things, depending on the testing of other family members: 

• If a mutation hasn’t been confirmed in another family member, a negative result is considered uninformative because you may have either not inherited the mutated gene or the cancers in your family weren’t a result of a mutation tested in your genetic test. In these cases, your risk remains elevated for the cancers that run in your family. 
• If a mutation has been confirmed in another family member, you don’t have a higher risk of developing breast or ovarian cancer than the average person. A Variant of Uncertain Significance Result

The final result you might receive is a variant of uncertain significance (VUS) result, which means the test detected a mutation in a gene associated with hereditary breast and ovarian cancer. However, whether that particular mutation causes cancer remains unknown. 

With this result, you’re still considered at an increased risk of cancers that run in your family. 

Breast Cancer Genetic Testing: A Piece of the Cancer Prevention Puzzle

Preventing and diagnosing breast cancer early involves a range of approaches. It starts with healthy lifestyle choices, like maintaining a healthy weight, exercising regularly, and limiting or avoiding alcohol. It continues by staying in close contact with your care team, staying up to date with recommended screenings, and reporting anything concerning to your healthcare provider.

For some people, it also involves genetic testing. Whether or not genetic testing is a part of your cancer prevention puzzle, you can be confident that your healthy lifestyle choices can help reduce your risk of breast cancer or catch it early when it’s easiest to treat.