Few medical tests feel quite as personal as genetic testing.

This isn’t just a picture of an organ or a number in your blood work.

This is your DNA.

So when a healthcare professional suggests genetic testing, it is easy to imagine that the result will reveal something absolute about your future.

You have the gene, so you will get the disease.

Or:

You don’t have the gene, so you’re safe.

Genetics is rarely that simple.

Genetic testing can provide enormously valuable information.

But depending on the test and the condition being investigated, it may provide an answer, estimate a risk, identify something you carry, or leave you with a result that science doesn’t yet completely understand.

Before having genetic testing, one of the most important things to understand is:

What question is this particular test trying to answer?

What Is Genetic Testing?

Genetic testing looks for changes—often called variants—in genes, chromosomes, or other genetic material.

Those changes may help healthcare professionals understand whether someone has a particular inherited condition, carries a genetic variant that could be passed to a child, or has an increased likelihood of developing certain conditions.

Genetic testing may also sometimes help guide medical treatment.

But there are many different genetic tests.

Having “genetic testing” doesn’t mean every gene in your body is being examined for every possible disease.

The test has a purpose.

Understanding that purpose matters.

A Genetic Risk Is Not Always a Prediction

Suppose testing identifies a genetic variant associated with an increased risk of developing a particular disease.

That can be important information.

But increased risk does not necessarily mean certainty.

For many conditions, genes are only part of the story.

Other genetic factors, age, environment, lifestyle, medical history, and factors we don’t yet completely understand may also influence whether a disease develops.

Even when a genetic variant is strongly associated with a condition, the test may not be able to tell you exactly when symptoms will begin, how severe they will be, or how a condition will progress.

DNA can provide information about your future.

It does not always write the entire future for you.

Positive Doesn’t Always Mean “You Have It”

Just as with other diagnostic tests, the word positive needs context.

Depending on why testing was performed, a positive result might:

Confirm a suspected genetic condition.

Identify a genetic variant associated with increased disease risk.

Show that you are a carrier of a particular inherited condition.

Provide information that may influence screening or treatment.

Or indicate that other members of your biological family may want to discuss the finding with their own healthcare professionals.

So if you’re told your genetic test is positive, ask:

“What does positive mean in this particular test?”

That question matters much more than the word itself.

And Negative Doesn’t Always Mean “Nothing Genetic Is Going On”

A negative result can be reassuring.

But its meaning depends on what was tested.

Some genetic tests look for a very specific variant.

Others examine multiple genes.

And our understanding of genetics continues to evolve.

A negative result may mean that the particular genetic change being investigated wasn’t found.

It doesn’t necessarily mean that every possible genetic explanation has been eliminated.

Ask:

“What does this negative result rule out—and what doesn’t it rule out?”

That’s a much more useful way to understand the result.

Sometimes the Answer Is: We Don’t Know

This may be one of the most frustrating genetic test results:

Variant of uncertain significance.

Often shortened to VUS, this means a genetic difference was identified, but there isn’t currently enough evidence to determine whether that particular change is related to disease.

Think about what that means.

The laboratory found something.

But science doesn’t yet know exactly what to make of it.

That can be unsettling.

It is also an important reminder of where we are in genetics.

We know an extraordinary amount about human DNA.

We do not know everything.

An uncertain result should not be transformed into a diagnosis simply because a variation was found.

Your Results May Say Something About Your Family

Most medical tests tell us primarily about the person being tested.

Genetic testing can be different.

You share genetic material with your biological relatives.

So sometimes a finding in you may have implications for your parents, siblings, children, or other relatives.

That can create complicated emotions.

Do I tell my children?

Should my siblings be tested?

What if someone doesn’t want to know?

What if I learn something I wish I didn’t know?

These aren’t merely laboratory questions.

They’re human questions.

And they are one reason genetic counseling can be so valuable.

What Does a Genetic Counselor Do?

A genetic counselor is specially trained to help people understand genetic conditions, testing, risks, and results.

Importantly, that conversation can happen before testing.

A genetic counselor can help you understand:

What the test is looking for.

What kinds of results you might receive.

What a positive or negative result could mean.

Whether you might receive an uncertain result.

What the information could mean for family members.

And how the result might—or might not—change your medical care.

Sometimes understanding the possible answers before taking the test is just as important as understanding the result afterward.

Think About What You Want to Know

We often assume that more health information is always better.

But genetic information can be different because some results may tell you about risks that cannot currently be prevented or treated.

People vary enormously in how they feel about knowing that information.

One person may say:

“I want to know everything I possibly can.”

Another may say:

“If knowing won’t change anything medically, I’m not sure I want that information.”

Those are deeply personal decisions.

The important thing is to understand what information a test might reveal before agreeing to it.

What About Genetic Tests You Buy Yourself?

Direct-to-consumer genetic testing has made DNA information available outside the traditional healthcare setting.

These tests can provide interesting information about ancestry, traits, and in some cases certain health-related genetic variants.

But consumer testing and clinical genetic testing aren’t necessarily the same thing.

A consumer test may examine only selected variants rather than every genetic change associated with a particular condition.

So a result from a home testing kit should not automatically become a medical diagnosis—or a reason to panic.

If a consumer genetic result concerns you, take the actual report to a qualified healthcare professional and ask whether clinical confirmation or further evaluation is appropriate.

Ask One Important Question Before Testing

Throughout this series, we have returned to the same idea:

What will we do with the answer?

That question may be especially important with genetic testing.

If the result is positive, will your screening change?

Will treatment change?

Will other testing be recommended?

Could the result matter to family members?

If the result is negative, what does that actually exclude?

And if the result is uncertain, what happens then?

You deserve to understand those possibilities before your DNA is tested—not only afterward.

Your DNA Is Information, Not Your Identity

Genetic science has given medicine extraordinary new tools.

We can identify inherited disorders.

Recognize certain disease risks.

Help families understand conditions that have affected generations.

Sometimes tailor prevention, monitoring, or treatment using genetic information.

And our ability to interpret the human genome continues to grow.

But a genetic result is still a piece of medical information.

It does not describe everything about your health.

It cannot always predict what will happen to you.

And it certainly does not define who you are.

So if genetic testing becomes part of your healthcare, don’t be afraid to ask:

Why are we doing this test?

What exactly are we looking for?

What could the different results mean?

Will knowing the answer change my care?

Could the result affect my family?

And perhaps most importantly:

“Is there anything this test cannot tell me that I might assume it can?”

Because genetic testing can reveal remarkable things.

Understanding its limits is part of understanding its power.

References

MedlinePlus Genetics, National Library of Medicine. What Is Genetic Testing?

MedlinePlus Genetics, National Library of Medicine. What Do the Results of Genetic Tests Mean?

MedlinePlus Genetics, National Library of Medicine. What Are the Risks and Limitations of Genetic Testing?

MedlinePlus, National Library of Medicine. Genetic Testing.