BRCA1 & BRCA2.
Breast Cancer Susceptibility Genes
Essential DNA repair genes. Mutations significantly increase cancer risk—but knowledge is power.
Important: This is educational information.
BRCA testing and management decisions should be made with genetic counselors and healthcare providers. If you have concerns about hereditary cancer risk, please seek professional genetic counseling.
The numbers.
What BRCA genes do.
BRCA1 and BRCA2 are tumor suppressor genes. They're essential for repairing damaged DNA, especially double-strand breaks.
BRCA functions:
- ✓Repairs double-strand DNA breaks (the most dangerous type)
- ✓Maintains genomic stability during cell division
- ✓Suppresses tumor formation
- ✓Works in homologous recombination repair pathway
- ✓Essential for healthy cell replication
When BRCA is mutated
With a BRCA mutation, cells can't properly repair DNA damage. Over time, errors accumulate, increasing the chance that a cell becomes cancerous. It's like having a spellchecker that misses most errors—eventually, serious mistakes get through.
Should you consider testing?
Family history pattern
- •Multiple relatives with breast or ovarian cancer
- •Cancer at young ages (under 50)
- •Male breast cancer in family
- •Same person with multiple cancers
- •Ashkenazi Jewish ancestry
When to consider testing
- •Known BRCA mutation in family
- •Breast cancer before age 50
- •Triple-negative breast cancer
- •Ovarian cancer at any age
- •Male breast cancer
- •Multiple breast cancers
The role of genetic counseling
Genetic counselors help interpret family history, explain testing options, discuss implications of results, and guide decision-making. They're essential partners in this process—not just for testing, but for understanding what results mean for you and your family.
BRCA mutation ≠ Cancer.
A BRCA mutation significantly increases risk, but it doesn't guarantee cancer. Many people with BRCA mutations never develop cancer, and those who do often catch it early with proper surveillance.
Important perspectives:
- ✓Risk, not destiny: 55-72% risk means 28-45% of BRCA1 carriers won't get breast cancer
- ✓Knowledge enables action: Surveillance and prevention strategies significantly improve outcomes
- ✓Environment still matters: Lifestyle factors can modify genetic risk
- ✓Treatment advances: PARP inhibitors specifically target BRCA-mutated cancers
Management options.
If you carry a BRCA mutation, you have options. There's no single right answer—decisions depend on your values, circumstances, and risk tolerance.
Enhanced Surveillance
- •Annual breast MRI starting at age 25-30
- •Annual mammogram starting at age 30
- •Clinical breast exams every 6-12 months
- •Consider transvaginal ultrasound for ovaries
Risk-Reducing Medications
- •Tamoxifen or raloxifene may reduce breast cancer risk
- •Oral contraceptives may reduce ovarian cancer risk
- •Must weigh benefits vs side effects
Risk-Reducing Surgery
- •Prophylactic mastectomy reduces breast cancer risk by ~90%
- •Prophylactic oophorectomy reduces ovarian cancer risk by ~80%
- •Deeply personal decision—not required
- •Timing considerations (family planning, etc.)
The bigger picture.
Most breast cancer isn't hereditary
Only 5-10% of breast cancers are caused by inherited mutations like BRCA. Most breast cancer is sporadic—caused by acquired mutations over time, influenced by environment and lifestyle.
Negative test doesn't mean no risk
A negative BRCA test doesn't eliminate breast cancer risk—it just means you don't have those specific high-risk mutations. General population screening recommendations still apply.
Men can carry and be affected
Men can inherit and pass on BRCA mutations. Male BRCA2 carriers have increased risk of breast, prostate, and pancreatic cancer. Family history on the father's side matters too.
Resources.
If you're exploring BRCA testing or have received results, these resources can help.
Find a genetic counselor
The National Society of Genetic Counselors (NSGC) has a directory at FindAGeneticCounselor.com
FORCE (Facing Our Risk of Cancer Empowered)
Support community for people with hereditary cancer risk. Offers peer support, research updates, and resources.
High-risk breast clinics
Many cancer centers have specialized clinics for people with hereditary cancer syndromes, offering comprehensive surveillance and management.
Related reading.
Knowledge is power.
Understanding your genetic risk allows you to take control. Early detection and prevention strategies save lives.