The short explanation
If your sister carries a BRCA1 change, you have about a one in two chance of having inherited the same change. Testing can tell you whether you do. A positive result does not mean you have cancer or that you will definitely get it. It means your lifetime risk of breast and ovarian cancer is much higher than average, which opens up options to find problems early or lower the risk. A negative result for the specific change found in your sister usually means your risk is closer to that of the general population, though screening still applies.
What depends on your situation
The parts of this that change from woman to woman. Uncertainty is stated, not hidden.
- Testing is best done with genetic counselling before and after, so you understand what each result would mean for you, your children and other relatives. Large hospitals and cancer centres in India increasingly have genetic counsellors.
- If you test positive, options a doctor may discuss include earlier and more frequent screening, sometimes with MRI, and preventive surgery for some women, timed with family plans. These are personal decisions with no single right answer.
- Questions about insurance and how relatives may react are common and fair to raise with the counsellor.
What this answer cannot determine
The boundary of online education. These need a clinician who can see you.
- This cannot tell you your result or your personal risk. Testing and counselling with your family history in front of the team answer that.
Questions for your clinician
Take these with you. You can add any of them to an appointment card.
- Can I see a genetic counsellor before deciding to test?
- Which specific gene change should my test look for?
- If I test positive, what screening would you recommend and from when?
- What would a result mean for my children?
When to seek help
Clinician-approved guidance for this topic. When in doubt, being seen is never the wrong choice.
Book an appointment soon
- See a clinician within days if you notice any breast lump or change while waiting.
Raise it at a routine appointment
- Book genetic counselling through your sister's treating hospital or a cancer centre, and take a copy of her report.
Sources
The evidence this explanation is built on.
- BRCA gene changes: cancer risk and genetic testing National Cancer Institute
- Breast cancer MedlinePlus (NIH)
- Breast cancer World Health Organization
Who wrote and reviewed this
Every AskHer answer names its author. A clinically reviewed answer also names the clinician who signed it off — if no clinician is named below, it has not been clinically reviewed.
- Author
- AskHer Editorial (AI-assisted draft) AskHer's editorial team — not an individual clinician Works in English, தமிழ், हिन्दी
- Clinical reviewer
- Nobody yet No clinician has signed this answer off, and no person on the editorial team has read it yet. That is what the “Written with AI assistance” label means. It is queued for an editor to read, and then for a clinician who works in this area. The sources it was drafted against are listed above.
- Review status
- Written with AI assistance — not yet reviewed by a person
- Last reviewed
- Not yet reviewed by a person
- Version
- 1
Correction history
Substantive changes are listed, not quietly edited away.
No corrections have been made since this answer was first published.
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