What BRCA1 and BRCA2 are — and aren't
BRCA1 and BRCA2 are tumor suppressor genes. In their normal form, they help repair DNA damage and prevent cells from dividing uncontrollably. Certain inherited mutations in these genes impair that repair function. The result is a significantly elevated lifetime risk of breast cancer, ovarian cancer, and several other cancers.
The important framing: a BRCA mutation doesn't mean you will get cancer. It means your risk is substantially higher than average, and that the odds are weighted differently across your lifetime. Most BRCA mutation carriers do not develop cancer by their 40s. The mutation shifts probability, not certainty. What it does is give you information — which is actionable in ways that waiting and hoping is not.
Who should think about testing
BRCA testing isn't recommended for the general population without elevated risk. But the definition of "elevated risk" has been evolving. The USPSTF recommends that primary care clinicians use a validated risk assessment tool (like the Ontario Family History Assessment Tool or Manchester Scoring System) for women with personal or family history suggesting elevated risk, and refer those who screen positive for genetic counseling.
Risk factors that warrant a conversation with your doctor about BRCA assessment include: a close relative (parent, sibling, child) with a known BRCA mutation; a personal history of breast or ovarian cancer; Ashkenazi Jewish ancestry (where BRCA mutation prevalence is approximately 1 in 40, compared to 1 in 400 in the general population); a family history of early-onset breast cancer (before 50), bilateral breast cancer, or male breast cancer; or a family pattern of both breast and ovarian cancers.
The 2025 NCCN Clinical Practice Guidelines (Version 2.2025) made a meaningful change: the family history requirement was removed for people with BRCA2 mutations specifically. This means that individuals with BRCA2 mutations — even without a significant family history — now qualify for the enhanced management recommendations in the guidelines. The change reflects growing evidence that hereditary cancer syndromes are more prevalent and more varied in their family presentation than earlier models assumed.
What a positive result actually means — and your options
A positive BRCA1 or BRCA2 result opens a specific menu of risk management options. None are mandatory. All are decisions made in conversation with your medical team and oncologist. The options include: enhanced surveillance (starting breast MRI at 25–30 alongside annual mammography, earlier than standard screening); risk-reducing medications (tamoxifen or raloxifene, which studies show can reduce breast cancer risk by 30–50% in high-risk women); and risk-reducing surgery (bilateral mastectomy or salpingo-oophorectomy for BRCA carriers who meet criteria).
Preventive surgery is not the only option, and it's not the right option for every BRCA-positive woman. The decision depends on your age, which mutation you carry, your personal and family history, and your own preferences and risk tolerance. Genetic counseling — before and after testing — is the appropriate support structure for navigating this. Not a Google search and not a direct-to-consumer BRCA test result without clinical follow-up.
Tests like 23andMe that include BRCA variant screening look for only three specific variants that are most common in the Ashkenazi Jewish population. They do not screen for all known BRCA1/2 pathogenic variants — there are hundreds. A negative result on a DTC test is not a clean bill of health. A positive result on a DTC test still requires confirmation with a clinical genetic test before any medical decisions are made. If you have a family risk profile that warrants testing, a clinical genetic counselor is the right starting point, not a kit.
What to tell your OB-GYN or primary care doctor
- Come prepared with your family history on both maternal and paternal sides: breast cancer, ovarian cancer, age at diagnosis, and any known genetic testing in relatives.
- Ask whether your family history warrants formal risk assessment using a validated tool. This is a 5-minute conversation that your primary care provider can initiate.
- If risk assessment suggests elevated likelihood, ask for a referral to a genetic counselor — not just a genetic test. Counseling before testing is standard of care, because the results require interpretation and emotional preparation.
- If you're Ashkenazi Jewish and haven't discussed BRCA risk with your doctor, bring it up. The 1 in 40 prevalence in that population is a clinically relevant factor that warrants a conversation even without a notable family history.
If you already have a BRCA result from a DTC test
A positive DTC BRCA result needs clinical confirmation through a medical-grade diagnostic test before any management decisions are made. False positives and variants of uncertain significance require interpretation by a genetic counselor. If your result came back positive on a consumer test, ask your primary care provider or OB-GYN for a referral to a certified genetic counselor as the next step — not directly to a surgeon.
References
- National Cancer Institute. BRCA Gene Changes: Cancer Risk and Genetic Testing. cancer.gov
- USPSTF. BRCA-Related Cancer: Risk Assessment, Genetic Counseling, and Genetic Testing. Recommendation Statement. uspreventiveservicestaskforce.org
- NCCN Clinical Practice Guidelines in Oncology. Genetic/Familial High-Risk Assessment: Breast, Ovarian, and Pancreatic, Version 2.2025. nccn.org
- ACOG FAQ: BRCA1 and BRCA2 Mutations. acog.org