What you need to know about DNA tests

Kylie Whalen, MS, LCGC CG(ASCP)CM, is a Senior Pediatric Genetic Counselor in Inova’s Genetics Department. Kylie received her bachelor’s in diagnostic genetic sciences with a concentration in cytogenetics at the University of Connecticut, and she maintains a current certification as a cytogenetic technologist. Kylie received her master’s in genetic counseling from Long Island University.

DNA tests offer more options than ever before

DNA testing, also known as genetic testing, has grown immensely over the last few decades. Genetic professionals can now choose from multiple different tests to help determine someone’s risk of developing cancer, heart problems or other diseases. Here are answers to commonly asked questions about DNA tests.

What is DNA testing?

DNA testing, also known as genetic testing, has exploded in popularity over the last few years. DNA tests are more affordable and accessible than ever before. But are they the right choice for everyone? Diagnostic genetic testing searches for mutations or changes in your DNA that can indicate the potential for disease. It can help providers determine the kind of medical care you should receive.

What is genetic counseling?

A genetic counselorhelps you decide if genetic testing is an option for you. You’ll meet with a counselor who will explore your medical and family history and go through the pros and cons associated with actually getting those test results. Once the decision is made to move forward with testing, your counselor will review the test results with you and guide you through next steps. Patients can be tested for a range of common conditions including:

  • Breast, colon, ovarian, uterine, and other cancers
  • Heart problems including arrythmias (issues with the heart rhythm), cardiomyopathy (a disease that affects the heart muscle) and conditions that result in very high cholesterol levels
  • Issues with children including heart defects, developmental problems, delayed motor skills or speech, autism, slow growth, seizures and epilepsy

What does it mean to be a carrier?

20,000 genes make up the human genome. Genes are made of DNA (the molecule that forms the genetic code) and serve as the instructions for your body’s growth and function:

  • Each one of us has two copies of every gene, one inherited from their mother and one inherited from their father
  • There are certain genetic conditions that will affect an individual if there is a variant or a mutation on both copies of the gene inherited from both parents (recessive). In that case, for a person with that variant on only one copy, they would be considered a carrier
  • As far as recessive genetic conditions are concerned, carriers generally don’t have any symptoms, but their children could inherit both variants if both parents are carriers   

Genetic testing at Inova vs. companies such as 23andMe

Inova’s general genetics team consists of six genetic counselors, two geneticists, two genetic counseling assistants, and a cardiogenetics coordinator focused on the following areas:

  • Pediatric genetics
  • Adult genetics
  • Cardio genetics
  • Prenatal genetics

Inova also has a separate team of nine genetic counselors dedicated to hereditary cancer genetics. The biggest difference in genetic testing at Inova and other health systems as opposed to 23andMe® and other direct-to-consumer (DTC) companies centers on the information that they’re allowed to review or report. Inova does clinical genetic testing for patients that are referred with the goal of a diagnosis.

DTC genetic testing companies are allowed to analyze certain genes or report certain types of changes in a gene, but they can’t tell you everything. Clinical genetic testing is a more comprehensive option for patients seeking a genetic diagnosis.

Testing breast cancer genes BRCA1 and BRCA2

One example of the difference between a health system such as Inova and a DTC is genetic testing for breast cancer risk. One DTC lab tests the two most common genes including BRCA1 and BRCA2 for only three mutations that appear more often in the Ashkenazi Jewish population. A clinical genetic testing lab on the other hand might analyze almost 20 different genes and test for thousands of mutations.

Is a blood sample more effective than saliva for testing?

Initially, genetic testing was done on blood, but tools have evolved. Specialists can now extract DNA from other cells in the body including a saliva sample or a cheek swab. These are done a lot, especially for kids, and are just as accurate. Inova collects samples in clinic and sends them to any one of a number of clinical genetic testing companies based on the particular test recommended for the patient. Once the results come back, the team:

  • Reviews the report with you
  • Clarifies ambiguous information
  • Determines next steps                    
  • Helps coordinate those next steps

Inova protects your personal health information

Inova utilizes only clinical genetic testing companies, not DTC companies. All personal health information is protected and none of those identifiers are ever shared.

Trends in the field of genetics

In the past we used to do smaller genetic tests because there were a lot of concerns around cost and insurance coverage. Now more insurance companies are recognizing genetics and genetic testing which has resulted in better coverage. We’re able to do bigger tests than we could in the past, which means we can offer patients a lot more options to take control of their healthcare.

Genetics will continue to be an important part of healthcare

DNA tests can help you develop a better understanding of conditions you and your family may be at risk for, and you can then work with your provider to chart a course of action for your healthcare.

If you are interested in DNA tests, learn more about Inova’s Genetic Programs

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