BRCA1 and BRCA2: Understanding Your Genetic Risk for Breast and Ovarian Cancer

When it comes to hereditary breast cancer and ovarian cancer, two genes often take center stage: BRCA1 and BRCA2. But what are these genes and what does it mean if you have a mutation? Understanding your genetic risk is a powerful step toward proactive health management.

What are BRCA1 and BRCA2 genes?

The BRCA1 (Breast Cancer gene 1)  and BRCA2 (Breast Cancer gene 2) genes are the primary tumour suppressors in your body. Each of these genes is present in two copies at birth. In essence, they serve as a vital defence mechanism against cancer by producing proteins that fix broken DNA and guarantee the steady proliferation of cells. This repair mechanism, however, malfunctions when a dangerous genetic mutation takes place in either of these genes, greatly raising a person's lifelong chance of getting some types of cancer.

How Mutations Increase Cancer Risk

A BRCA mutation is like a spelling error in the gene’s instruction manual. The gene is unable to operate properly because of this mistake. Unrepaired DNA damage increases the likelihood that cells will undergo further genetic changes that may cause cancer. There is a significantly increased risk of ovarian cancer (up to 44% for BRCA1 and 17% for BRCA2) and hereditary breast cancer (up to 72%) for women who have a deleterious BRCA1 or BRCA2 mutation. Male breast, pancreatic, and prostate cancers are among the various cancers for which these mutations raise the risk.

Who Should Consider Genetic Testing?

Genetic testing for BRCA1 and BRCA2 mutations is not recommended for the general public but is typically advised for individuals with a strong personal or family history indicative of hereditary cancer syndromes. Key indicators that warrant a discussion with a doctor or genetic counsellor include a personal or family history of breast cancer diagnosed at a young age (e.g., under 50), multiple relatives on the same side of the family with breast or ovarian cancer, a diagnosis of male breast cancer, Ashkenazi Jewish ancestry, or a population with a significantly higher founder mutation prevalence for BRCA1 and BRCA2 (National Comprehensive Cancer Network, 2023; American Cancer Society, 2022).

Implications for Family Members

These genetic mutations are hereditary can be inherited from either parent. Siblings and offspring have a 50% probability of inheriting the same mutation if a person tests positive. For whole families, genetic counselling and possible testing are therefore essential.

Treatment and Preventive Strategies

A positive test may not necessarily indicate the presence of cancer. Rather, it offers a chance for empowered, customised healthcare. Knowing one's BRCA status can affect treatment decisions, such as certain chemotherapies or surgical possibilities, for people who have already received a cancer diagnosis. Proactive preventive measures can greatly lower risk for healthy mutation carriers. These consist of risk-lowering drugs, preventive operations (such as mastectomy and salpingo-oophorectomy), and improved screening (such as yearly MRIs and mammograms).

Knowing your BRCA status gives you the ability to collaborate with your healthcare team to make well-informed decisions, transforming knowledge into an effective preventative and early detection tool.