BRCA2 6174delT — Ashkenazi founder variant
A BRCA2 6174delT variant has been detected.
You have a specific BRCA2 gene change that's well known for raising breast, ovarian, pancreatic, and prostate cancer risk.
A BRCA2 pathogenic variant associated with substantially elevated lifetime risks of breast (~69%), ovarian (~17%), pancreatic, and prostate cancers. Clinical confirmation and genetic counselling are essential.
If you were assigned female at birth, your lifetime risk is around 69% for breast cancer and 17% for ovarian cancer. Risks for pancreatic and prostate cancer are also raised, and male breast cancer risk is higher than average. Confirm the result with a clinical lab and speak to a genetic counsellor before acting on it.
What this means
6174delT is the most common Ashkenazi Jewish founder variant in BRCA2. Like other BRCA2 pathogenic variants it impairs DNA repair, particularly homologous recombination. Cancer risks are slightly different from BRCA1 (lower ovarian cancer risk, similar breast cancer risk, higher male breast cancer risk). PARP inhibitors are particularly effective in BRCA2-mutated cancers — relevant to know if a diagnosis is ever made.
This is the most common BRCA2 change in people of Ashkenazi Jewish ancestry. BRCA2 normally helps cells repair broken DNA, and a damaged copy raises lifetime cancer risk. The pattern is a little different from BRCA1: ovarian cancer risk is lower, breast cancer risk is similar, and male breast and prostate cancer risk are higher. There's also a useful treatment angle — a class of drugs called PARP inhibitors works particularly well against BRCA2-related cancers, which is worth knowing if a diagnosis is ever made.
Caveats
- Confirm with a clinical-grade laboratory before acting.
- A negative chip result does not rule out other BRCA1/BRCA2 variants.
- Male carriers should be aware of increased male breast and prostate cancer risk.
- Genetic counselling is strongly recommended.
Populations
- Ashkenazi Jewish populations (~1.5% allele frequency)