Predictive BRCA Testing: What to Expect Before You Test

Quick answer: Predictive BRCA testing determines whether you've inherited a BRCA1 or BRCA2 mutation that may increase your risk of certain cancers, particularly breast and ovarian cancer. It's typically considered by people with a family history of these cancers or a known BRCA mutation in a relative. The process involves genetic counselling, a blood or saliva sample, and one of three possible outcomes: positive, negative, or a variant of uncertain significance (VUS).

If you're weighing whether to pursue this test, it can help to understand exactly what it involves and what each possible result actually means — before you're sitting in the appointment.

What Is the Purpose of Predictive BRCA Testing?

Predictive testing is conducted to determine whether an individual has inherited a BRCA mutation that may increase their risk of developing certain cancers, particularly breast and ovarian cancer. Unlike diagnostic testing, which is used after a cancer diagnosis to guide treatment, predictive testing looks ahead — helping you understand your risk before any cancer develops.

Who Should Consider Predictive BRCA Testing?

Predictive testing is generally recommended for:

• Individuals with a family history of breast, ovarian, or related cancers.
• Individuals who have a known BRCA mutation in a family member — since relatives typically have around a 50% chance of carrying the same mutation.

If either of these applies to you, a conversation with a genetic counselor is the natural starting point, even before you decide whether to test.

How Does the Predictive BRCA Testing Process Work?

1. Genetic counselling. Before testing, individuals usually undergo genetic counselling to assess their personal and family cancer history and understand what the results could mean for them.

2. Sample collection and testing. A blood or saliva sample is collected and analysed in a lab for BRCA mutations.

3. Results and next steps. Your genetic counsellor will help you interpret the result and talk through what, if anything, to do next.

What Do Predictive BRCA Test Results Mean?

There are three possible outcomes from predictive testing:

Positive Result

A positive result indicates the presence of a BRCA mutation, suggesting an increased risk for certain cancers. This information can guide proactive measures such as enhanced screening, preventive surgeries, or lifestyle changes. If you've just received this result, our guide on what a positive BRCA result means walks through what happens next.

Negative Result

A negative result indicates no BRCA mutation was found. Importantly, this does not eliminate the risk of developing breast or ovarian cancer, since other genetic or environmental factors may still be involved. A negative result is reassuring, but it isn't a guarantee.

Variant of Uncertain Significance (VUS)

A VUS result means a genetic change was found, but it isn't clearly associated with an increased cancer risk. This outcome requires further monitoring and research — as scientific understanding improves, a VUS may eventually be reclassified as either benign or harmful. Your genetic counsellor can explain how your specific variant is currently understood and what monitoring, if any, makes sense in the meantime.

What Happens After Your Result?

Whatever the outcome, your genetic counsellor will help translate the result into a plan:

• Positive results may lead to conversations about enhanced screening, risk-reducing surgery, or lifestyle adjustments.
• Negative results may still involve ongoing awareness of family history and standard screening guidelines.
• VUS results typically call for continued monitoring, with the possibility of updated information as research progresses.

Making the Decision to Test

Predictive BRCA testing is a personal decision, and there's no obligation to test just because you're eligible. Talking it through with a genetic counsellor beforehand ensures you understand not just the mechanics of the test, but what each possible outcome could mean for you and your family — so that whichever result comes back, you're prepared rather than blindsided.

Frequently Asked Questions

What is predictive BRCA testing used for?

Predictive BRCA testing checks whether someone has inherited a BRCA1 or BRCA2 mutation that could increase their risk of breast, ovarian, or related cancers, before any cancer has developed.

Who should get predictive BRCA testing?

It's generally recommended for people with a family history of breast, ovarian, or related cancers, or those with a known BRCA mutation in a close family member.

What does a negative BRCA test result mean?

A negative result means no BRCA mutation was found. However, it doesn't rule out cancer risk entirely, since other genetic or environmental factors can still play a role.

What is a Variant of Uncertain Significance (VUS)?

A VUS is a genetic change that isn't currently known to be linked to increased cancer risk. It requires ongoing monitoring, and may be reclassified over time as research advances.

How is predictive testing different from diagnostic testing?

Predictive testing is used before a cancer diagnosis to assess future risk, often based on family history. Diagnostic testing is used after a cancer diagnosis to help guide treatment decisions.

This article is intended for general educational purposes and is not a substitute for personalized medical advice. Please speak with a genetic counsellor about whether predictive BRCA testing is right for you.