What Are BRCA1 and BRCA2?
BRCA1 and BRCA2 are genes that help repair damaged DNA and protect cells from developing cancer.
Everyone has these genes. However, some people inherit harmful changes, known as pathogenic variants, that reduce their ability to repair DNA effectively.
These inherited changes can significantly increase the risk of certain cancers, particularly breast and ovarian cancer.
They are also associated with increased risks of some prostate and pancreatic cancers.
How Much Can BRCA Changes Increase Cancer Risk?
Women who inherit a harmful BRCA1 or BRCA2 variant have a substantially higher lifetime risk of breast cancer than women in the general population.
The risk of ovarian cancer is also increased, particularly with BRCA1 variants.
Men who carry certain BRCA variants may have an increased risk of prostate cancer and male breast cancer.
However, carrying a harmful BRCA variant does not mean that cancer will inevitably develop.
The individual risk depends on the specific gene, family history, age, and other factors.
Who Should Consider BRCA Genetic Testing?
BRCA testing may be appropriate for people with certain personal or family cancer histories.
Examples include breast cancer diagnosed at a young age, ovarian cancer, male breast cancer, pancreatic cancer, or a known BRCA variant in the family.
Some people diagnosed with breast or prostate cancer may also meet criteria for testing based on their diagnosis and clinical characteristics.
BRCA variants can be inherited from either parent. Each child of a parent carrying an inherited pathogenic BRCA variant has a 50% chance of inheriting it.
A genetic specialist can help determine whether BRCA testing alone or a broader hereditary cancer panel is more appropriate.
What Does a Positive or Negative Result Mean?
A positive result identifies an inherited harmful BRCA variant associated with increased cancer risk.
A negative result requires careful interpretation. If a known familial variant is absent, this can provide important reassurance about that specific inherited risk.
However, a negative result does not eliminate the possibility of cancer or exclude all hereditary cancer syndromes.
Sometimes testing identifies a variant of uncertain significance. This means there is not enough evidence to determine whether the change increases cancer risk.
Such findings should not independently guide major preventive decisions.
How Can BRCA Testing Help Prevent Cancer?
For people with confirmed harmful BRCA variants, knowing their genetic risk can lead to a more personalized prevention plan.
Depending on the individual situation, doctors may recommend earlier breast screening, regular breast MRI, or other risk-adapted surveillance.
For selected high-risk individuals, preventive medication or risk-reducing surgery may also be considered.
Some interventions reduce the likelihood of developing cancer. Others aim to detect cancer earlier, when treatment may be more effective.
Family members may also benefit from targeted testing for the same inherited variant.
