A BRCA test is a genetic assessment identifying inherited changes in the BRCA1 and BRCA2 genes. These genes are associated with an increased risk of breast, ovarian, and other related cancers. The test offers insights into a person’s genetic predisposition, aiding informed decisions for cancer risk management. It helps understand one’s inherited risk profile, rather than diagnosing an existing cancer.
Understanding BRCA Genes
Everyone has two copies of the BRCA1 (BReast CAncer gene 1) and BRCA2 (BReast CAncer gene 2) genes, one from each parent. These genes function as tumor suppressors, producing proteins that help repair damaged DNA. This DNA repair is important for maintaining genetic stability, preventing uncontrolled cell growth and tumor formation.
When a harmful change, or pathogenic variant, occurs in a BRCA1 or BRCA2 gene, its ability to repair damaged DNA is impaired. Cells become less effective at fixing genetic errors, which accumulate. This increases the risk of certain cancers. These inherited variants are present in every cell from birth.
Purpose and Eligibility for Testing
BRCA testing assesses an individual’s inherited risk for specific cancers, including breast, ovarian, prostate, pancreatic, and sometimes melanoma. It helps individuals and healthcare providers develop personalized strategies for early detection or risk reduction.
Eligibility for BRCA testing considers a strong personal or family history of these cancers. Criteria include breast cancer diagnosed before age 50, triple-negative breast cancer, or multiple primary breast cancers. Ovarian, fallopian tube, or peritoneal cancer at any age also warrants consideration.
Family history is a significant factor, such as multiple relatives on the same side of the family with breast or ovarian cancer, especially if diagnosed young. Other considerations include male breast cancer, a known BRCA mutation in a close blood relative, or Ashkenazi Jewish ancestry. A healthcare provider or genetic counselor can help determine if testing is appropriate.
The Testing Process
A BRCA test begins with a genetic counselor consultation. The counselor discusses testing implications, including potential results, personal cancer risk, and family implications. This session helps individuals make an informed decision.
The test is straightforward, requiring a small blood or saliva sample. For blood, a healthcare professional draws a sample from a vein. For saliva, the individual provides it by spitting into a container.
Once collected, the sample is sent to a specialized laboratory for DNA analysis. The lab examines DNA for changes or mutations within BRCA1 and BRCA2 genes. Results can take several weeks or months.
Interpreting and Acting on Results
BRCA test results are categorized into three main types, each with distinct implications for health management. A genetic counselor or healthcare provider explains these results and guides subsequent steps.
A positive result, termed “pathogenic” or “likely pathogenic variant,” indicates a harmful mutation in BRCA1 or BRCA2. This signifies an increased lifetime risk of developing cancers like breast, ovarian, prostate, and pancreatic. Management options include enhanced cancer screening (e.g., earlier, more frequent mammograms and breast MRIs). Preventive surgeries, such as a risk-reducing mastectomy or removal of ovaries and fallopian tubes (salpingo-oophorectomy), can considerably reduce cancer risk. Chemoprevention, using certain medications to lower cancer risk, may also be discussed.
A negative result means no harmful mutation was found in the tested BRCA genes. While this indicates a risk similar to the general population for BRCA-related cancers, it does not eliminate all cancer risk. Other genetic factors, lifestyle choices, and environmental exposures can still contribute to cancer. General cancer screening guidelines and healthy lifestyle practices remain important.
A variant of uncertain significance (VUS) indicates a gene change with unclear health impact. Researchers lack enough information to classify these variants as harmful or benign. VUS results do not immediately change medical management; individuals follow standard cancer screening based on personal and family history. These variants are sometimes reclassified as more data becomes available.