Genetic testing can be an incredibly helpful tool in diagnosing and treating a variety of conditions, from cancer and blood disorders to rare diseases. And it’s often as easy as swabbing your child’s cheek. Still, sometimes the first time parents and caregivers hear about it is when their child already needs it.

As genetic testing becomes more and more common, our experts aim to make sure parents know what it is, how it works and why it’s especially helpful in pediatrics.

“Genetic medicine touches all areas of medicine, from prenatal to pediatric through adult and geriatric. Genetics also impacts every single body system that I can think of,” says Margarita Saenz, MD, a clinical geneticist at Children’s Hospital Colorado. “So as this evolves and expands, I think it's important for people to have an awareness that precision medicine can and will be integrated into more general medical care as we go forward.”

What are genetic conditions?

First, we need to understand what genetic conditions are. Genetic conditions occur because of a change in your child’s DNA that impacts its function. The difference between inherited conditions and other types of genetic conditions is in how that change came to be.

Inherited conditions are caused by a genetic change that is passed down from parent to child.

Other genetic conditions are caused by a new genetic change in a child’s DNA that does not run in the family. Genetic testing can help us find the cause of both inherited and noninherited genetic conditions. Family history is an important part of genetic testing, but it does not tell us the whole story.

How does genetic testing work and what is genetic testing?

Genetic testing is a medical tool that looks for changes in your child’s DNA. DNA is a molecule in our cells. It gives the body instructions on how to build proteins. Our bodies use these proteins in many different ways to function properly. When there are changes in the DNA, it’s like having instructions that are confusing, missing parts or in the wrong order. This means our bodies don’t know how to make important proteins.

When your child gets genetic testing, we take a sample of their cells and separate out the DNA using special machines. We usually take a swab of the inside of their cheek, but sometimes we need other samples, such as blood.

“This type of genetic testing is different than Ancestry.com or 23andMe, where you find out about family members you may not know about, and that genetic information is not protected like a medical test result,” Dr. Saenz says. “This is a medical test that lives within our laboratory, where everything is in-house. As a  medical test, it has Health Insurance Portability and Accountability Act (HIPAA) protections so others are not allowed access to that information.”

What genetic testing is

When we do genetic tests, we can use your child’s DNA sample to learn specific things about their body’s makeup and how it operates. More specifically, we can look at their DNA to understand any differences from the norm. For example, those can include (but aren’t limited to) anything that’s:

• Added
• Changed
• Missing
• In a different order than expected

What genetic testing is not

• Genetic testing is not a genealogy test. Many of the  tests you can buy and use at home are designed to track your family’s ancestry. Genealogy tests are different from clinical genetic tests because they are not designed for medical decision-making. They can also give incomplete or misleading results.
• Genetic testing is not a paternity test. Sometimes we recommend that parents and family members get genetic testing so we can interpret the patient’s genetic information better. These tests can give us biological information, but they are not the same as a paternity test.
• Genetic testing is not a publicly shared record. Any medical information we get through genetic testing is protected by HIPAA. That means we do not give your child’s test results to anyone outside our health system without your consent.

Why do doctors refer children for genetic testing?

When your care team refers your child for genetic testing, they are looking for more information about a possible or confirmed diagnosis. A referral does not always mean that your child has a specific condition. And it does not always mean that something is “wrong.” If your child does ever get a referral for genetic testing, you’ll work with a genetic counselor who is there to help your family navigate the ins and outs of testing and diagnosis.

Often, genetic testing referrals are just a part of a longer diagnostic and treatment journey. Common reasons for referrals to genetic testing:

• Birth differences, such as congenital heart problems or cleft lip/palate
• Developmental delays or autism spectrum disorders
• Family history of a known or suspected genetic condition
• Growth differences, such as short stature, poor weight gain or overgrowth
• Seizures, epilepsy, movement disorders and other neurological concerns
• Vision or hearing differences

The benefits of genetic testing in kids

Each child is unique, and you know your family’s situation best. If your child is referred for genetic testing, you’ll work with a genetic counselor to help you understand the possible benefits of genetic testing and weigh your options. Knowing these benefits helps you decide whether testing is right for your child.

“It can impact treatment. It can impact supportive interventions. It can guarantee access to certain types of care, say for kids that are hearing impaired or visually impaired,” Dr. Saenz explains. “The other reason that it's very important is we're living in the age of precision medicine with advancements in clinical trials, as well as things like repurposed drugs or even molecular therapies that are targeting treatments for the DNA and RNA of our patients. So I think it's super important to identify patients that could qualify for those emerging treatments.”

Potential benefits of getting a diagnosis through genetic testing

Sometimes, genetic testing finds or confirms a specific diagnosis. In these cases, genetic testing may help:

• Avoid tests that are unnecessary or repetitive
• Clarify your child’s prognosis (long-term outcomes) or help you plan for possible future health effects
• Guide your care team’s plan for managing and monitoring a condition, along with referrals to other specialists
• Identify opportunities to participate in clinical trials or research studies (if your family wants to)
• Inform family planning and clarify any risks to your child’s relatives or future family
• Make your child eligible for various medical and community resources
• Support access to certain therapies, insurance coverage or other services

Potential benefits when testing does not lead to a diagnosis

Even when genetic testing does not confirm a specific diagnosis, it can still offer benefits. Testing may help:

• Guide healthcare decisions in the future
• Inform further testing as science advances
• Provide reassurance
• Rule out certain genetic conditions

Even though genetic testing doesn't always lead to clear answers, it's a growing part of the medical journey for many families. Whether you end up needing it or not, it can be helpful to become educated on how it works and why it matters.

To learn more about genetic testing, read our full guide.