What is genetic testing?
Genetic testing is used to identify changes, such as a mutation, in a person’s genes, or extra genetic material in chromosomes that can lead to cancer, birth defects in a child or other health conditions. The results can help you learn whether you’re at risk of developing or passing on a genetic condition or disease, such as cancer, cystic fibrosis or Marfan syndrome.
Genetic testing is voluntary. It has benefits and limitations, so the decision to go through testing is personal. A genetic counselor can provide information and help you understand the emotional and social aspects of testing.
Types of genetic testing
There are many types of genetic tests, and no single test can detect all genetic conditions. Your healthcare provider can help you choose the right test based on your medical history, family background and the specific condition you're being tested for.
The various types of genetic tests look at:
- Genes: These tests examine DNA to find variations (mutations) in genes that can cause or increase the risk of genetic disorders. Tests can focus on a single gene, multiple genes or even a person’s entire genome.
- Chromosomes: These tests check all 23 of your chromosomes for large structural changes, like an extra or missing chromosome, which might cause a condition.
- Proteins: Biochemical tests measure the levels or activity of proteins and enzymes, as changes in these can signal genetic disorders. Conditions linked to abnormalities in these tests are called “metabolic” or “biochemical” disorders.
What conditions can be detected through genetic testing?
It's important to remember that genetic testing can identify some conditions, but not all of them. A positive result doesn’t always mean you will develop a condition. However, genetic testing can help confirm or rule out a variety of diseases and conditions, including:
- Down syndrome
- Huntington's disease
- Cystic fibrosis
- Sickle cell disease
- Phenylketonuria
- Colon cancer
- Breast cancer
Reasons for genetic testing
Diagnostic testing
If you have symptoms of a disease that might be caused by genetic changes (mutated genes), genetic testing can help confirm the diagnosis. For example, it can be used to diagnose conditions like cystic fibrosis or Huntington’s disease.
Presymptomatic and predictive testing
Predictive and presymptomatic tests look for gene changes (mutations) linked to disorders that show up later in life. These tests can be useful for people with a family history of a genetic disorder, even if they don’t have any symptoms yet.
Predictive testing can find mutations that increase the risk of conditions like certain cancers. Presymptomatic testing can show if someone will develop a genetic disorder, like hereditary hemochromatosis (a condition that causes too much iron), before symptoms appear.
The results can help people understand their risk and make informed decisions about their medical care, including routine care to minimize the risk of the effects of a condition.
Carrier testing
If you have a family history of a genetic disorder, like sickle cell anemia or cystic fibrosis, or belong to a group with a higher risk of certain genetic conditions, you might consider genetic testing before having children. Expanded carrier screening can check for genes linked to many genetic disorders and see if you and your partner are carriers for the same condition.
Pharmacogenetics
If you have a specific health condition or disease, genetic testing can help identify the medication and dosage that will work best for your unique genetic makeup. This type of testing, often called pharmacogenomic testing, examines how your genes affect how your body processes certain medications.
By understanding your genetic profile, healthcare providers can personalize your treatment plan, choosing medications that are more likely to be effective and avoiding those that could cause harmful side effects. For example, pharmacogenomic testing might be used to guide treatment for conditions like depression, cancer, heart disease or chronic pain. This approach helps ensure that your treatment is safe and tailored to your individual needs.
Prenatal testing
If you're pregnant, prenatal genetic testing can detect certain abnormalities in your baby’s genes, such as Down syndrome or trisomy 18. Traditional methods include blood marker tests or invasive procedures like amniocentesis, which involves collecting amniotic fluid and carries a small risk of complications.
A newer, noninvasive option called cell-free DNA (cfDNA) testing analyzes fragments of the baby’s DNA found in the mother’s blood. This simple blood test can be done early in pregnancy and provides highly accurate results without risking the baby’s safety.
These tests help parents make informed decisions and prepare for any necessary medical care or support for their baby.
Newborn screening
Newborn screening is the most common type of genetic testing. In the United States, every state requires testing for specific genetic and metabolic conditions in newborns. This testing is crucial because it can detect disorders like congenital hypothyroidism, sickle cell disease or phenylketonuria (PKU). Early detection allows immediate care and treatment, supporting healthier lives.
Preimplantation testing
Preimplantation testing, or preimplantation genetic diagnosis (PGD), is a technique used to reduce the chance of having a child with a specific genetic or chromosomal disorder. It is done on embryos created through assisted reproductive techniques (ART), such as in vitro fertilization (IVF).
IVF involves fertilizing eggs with sperm outside the body. During preimplantation testing, a few cells are taken from the embryos and analyzed for genetic changes. Only embryos without these changes are implanted in the uterus to start a pregnancy. This process helps parents reduce the risk of passing on certain genetic conditions.
Who should consider genetic testing?
When deciding whether to get a genetic test for yourself or a family member, it's important to consider both medical and emotional factors. Genetic testing can provide a diagnosis and help guide treatment, symptom management or lifestyle changes. However, it has limitations. For example, even if a mutation is found, the test can't predict when symptoms will appear, how severe they will be or how the condition will progress. Depending on the mutation detected, the test cannot always predict if you will ever experience symptoms. Additionally, a negative test result doesn't always rule out the risk of developing a condition.
Given the complexity of genetic testing, it’s essential to speak with a healthcare provider, such as a genetic counselor, to understand the potential benefits and risks, and to get answers to any questions before and after the test.
How to prepare for genetic testing
Before you get genetic testing, learn as much as possible about the process, potential results and your family’s medical history. Talk with your doctor about the risks and benefits of genetic testing and plan on getting genetic counseling so you know what to expect at every step.
The role of a genetic counselor
How is genetic testing done?
Before you have a genetic test, it’s important to understand how the test works, what it can and can’t tell you and what the results might mean. This process is called informed consent, where you are given information about the test and asked for permission to proceed.
If you decide to have genetic testing, your healthcare provider will help arrange the test, often during a genetic consultation. The test is typically done using a sample of blood, hair, skin, amniotic fluid (during pregnancy) or other tissue. For instance, a buccal smear uses a cotton swab to collect cells from the inside of your cheek. These samples are sent to a lab where technicians look for specific changes in DNA, chromosomes or proteins, depending on the suspected condition.
Newborn screening tests are done with a small blood sample taken from your baby’s heel. You’ll usually only receive the results if they are positive. If the test result is positive, additional testing is needed to find out if your baby has a genetic disorder.
Your doctor will look at the results, determine what they mean and share your results with you. Be sure to talk to your doctor and genetic counselor and ask questions about what the results mean and what steps you should take after receiving the results.
For example, you may need earlier, more frequent or different types of cancer screening. Or you may need to meet with a maternal-fetal medicine specialist or neonatologist to discuss care options for a congenital difference in your new baby.
What are the risks of genetic testing?
Genetic testing can provide meaningful information that empowers you or a loved one to take charge of the future. However, it does come with some risks. Genetic testing can cause psychological distress. Having a genetic mutation doesn’t mean you will develop a disease, but it can cause stress and anxiety as you weigh your options for treatment or prevention.
Genetic testing can also impact family relationships and come with social and financial risks. Discuss these potential risks with your doctor and genetic counselor before you proceed with testing. The more you know, the better you’ll feel about taking the next steps.
Find a genetic testing location near you
We help you get care at a location that fits your needs. We offer several locations for your care, including genetic testing in North and Central Texas.
Baylor Scott & White All Saints Medical Center - Fort Worth
1400 8th Ave , Fort Worth, TX, 76104
Baylor Scott & White Clinic - Temple
2401 S 31st St , Temple, TX, 76508- Monday: 8:00 am - 5:00 pm
- Tuesday: 8:00 am - 5:00 pm
- Wednesday: 8:00 am - 5:00 pm
- Thursday: 8:00 am - 5:00 pm
- Friday: 8:00 am - 5:00 pm
Baylor Scott & White Medical Center - College Station
700 Scott and White Dr , College Station, TX, 77845
Baylor Scott & White Medical Center - Grapevine
1650 W College St , Grapevine, TX, 76051
Baylor Scott & White Medical Center - Irving
1901 N MacArthur Blvd , Irving, TX, 75061
Baylor Scott & White Medical Center - Temple
2401 S 31st St , Temple, TX, 76508
Baylor Scott & White Medical Center - Waxahachie
2400 N Interstate 35E , Waxahachie, TX, 75165
Baylor University Medical Center, part of Baylor Scott & White Health
3500 Gaston Ave , Dallas, TX, 75246Hours of Operation
Hours of Operation
Office Hours
Frequently asked questions
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How long does genetic testing take?
Generally, genetic testing takes only a few minutes. Getting the results may take a few days to several weeks. Your doctor or genetic counselor will let you know how long it will take to receive your results.
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How much does genetic testing cost?
The cost of genetic testing depends on personal and family history, insurance coverage, the complexity of the test and other factors. The tests can cost anywhere from a few hundred to a few thousand dollars. If you’re considering genetic testing for cancer, your genetic counselor can help you navigate the costs and your insurance coverage.
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Is genetic testing covered by insurance?
Most private health insurers will cover some or all costs of the test depending on the type of insurance, your personal and family history and the test you have. Talk to your genetic counselor about potential costs and coverage.