Breast cancer is one of the most common cancers affecting women worldwide. In recent years, genetic testing has emerged as a powerful tool in assessing breast cancer risk, especially for those with a family history of the disease. One of the most well-known genetic markers for breast cancer risk is the BRCA gene mutation.
What is BRCA?
The BRCA1 and BRCA2 genes are responsible for producing proteins that help repair damaged DNA. In a healthy state, these genes act as tumour suppressors, helping prevent the development of cancer. However, when there is a mutation in either gene, the body’s ability to repair DNA is compromised — increasing the likelihood of certain cancers, particularly breast and ovarian cancer.
Women who carry a BRCA gene mutation have a significantly higher lifetime risk of developing breast cancer — up to 70% by age 80, compared to about 12% for women without the mutation. BRCA mutations also increase the risk of ovarian cancer and, to a lesser extent, pancreatic and prostate cancer in both men and women.
Who Should Consider BRCA Genetic Testing?
BRCA genetic testing is most often recommended for individuals with a family history of breast, ovarian, or other related cancers. Specific factors that may prompt consideration of testing include:
- A personal history of breast cancer diagnosed before age 50
- A family history of breast or ovarian cancer, particularly if multiple relatives have been affected
- Having a relative who has already tested positive for a BRCA mutation
- Being of Ashkenazi Jewish descent, as individuals from this group are at higher risk of carrying BRCA mutations
- A family history of male breast cancer
How Does BRCA Genetic Testing Work?
BRCA genetic testing is a simple process that typically involves providing a blood or saliva sample. The sample is analysed to detect any mutations in the BRCA1 or BRCA2 genes. If a mutation is found, it indicates an increased risk of breast cancer and other cancers. It’s important to note that not all women with BRCA mutations will develop cancer — and conversely, women without BRCA mutations can still develop breast cancer.
The Impact of Testing Positive for a BRCA Mutation
If you test positive for a BRCA gene mutation, knowledge is power. Armed with this information, you can take proactive steps to reduce your risk and potentially prevent cancer altogether:
Enhanced Surveillance: Women with BRCA mutations are typically advised to begin breast cancer screening at an earlier age — often starting in their 20s or 30s — with annual mammograms and breast MRI scans.
Chemoprevention: Some women may opt for medications such as tamoxifen or raloxifene to reduce the risk of developing breast cancer by blocking oestrogen receptors in breast tissue.
Risk-Reducing Surgery: For women with very high risk, preventive surgery is an option — including prophylactic mastectomy or prophylactic oophorectomy (removal of the ovaries to reduce ovarian cancer risk).
Lifestyle Modifications: Maintaining a healthy weight, regular physical activity, limiting alcohol, and avoiding smoking can all help lower overall cancer risk even with a BRCA mutation.
BRCA Testing for Family Members
One of the most important aspects of BRCA genetic testing is its implications for family members. If you test positive for a BRCA mutation, your children, siblings, and other relatives may also be at risk. Sharing this information with your family empowers them to consider testing and take informed preventive action — potentially saving lives.
Emotional Considerations of BRCA Testing
While BRCA genetic testing provides critical information, it also comes with emotional challenges. Learning you carry a BRCA mutation can lead to anxiety, fear, and uncertainty. It’s important to have a strong support system and to work closely with healthcare professionals who specialise in cancer genetics. Genetic counselling is recommended before and after testing.
Why Is BRCA Genetic Testing Important?
BRCA genetic testing enables early detection and prevention efforts. Early diagnosis is crucial in treating breast cancer successfully, and BRCA testing allows women to take proactive measures to protect their health. Testing can also inform treatment decisions for women already diagnosed with breast cancer — for example, some women may choose a bilateral mastectomy instead of a lumpectomy to reduce the risk of recurrence.
Know Your Hereditary Cancer Risk
OncoMap by MapmyGenome screens your genetic predisposition to hereditary breast cancer, ovarian cancer, and 15+ other cancer types — including BRCA1, BRCA2, and HRR gene panel analysis. With genetic counselling included.
