Ads for at-home whole genome sequencing (WGS) kits are across the internet. They sound simple. You order a kit, collect your DNA, and return everything for testing. Before long, you get answers online about your health. So, how well do these kits work? How do they compare to what happens when you see a genetic counselor or licensed clinical geneticist? In this blog, we explore how at-home DNA sequencing tests stack up against visiting a genetics clinic.

Types of At-Home DNA Tests

Before we get too far, it’s important to understand the types of at-home DNA tests. The most common DNA tests available focus on ancestry. These tests come from companies like 23AndMe and AncestryDNA. Their reports mention basic health traits and common genetic markers, but they don’t give detailed information about your health or medical conditions. These tests only look at certain parts of your genome to identify common gene variants and select DNA markers. Because of their limited analysis, these tests have low accuracy for finding rare or complex conditions and may miss serious mutations.

In comparison, tests from companies like Sequencing.com and Nebula Genomics utilize whole genome sequencing (WGS) technology to provide additional health information. Whole genome sequencing maps out the entire DNA sequence of your genome, rather than just looking at select areas. When completed and interpreted properly, WGS can provide incredibly detailed insights into your health and genetic risks.

Collecting DNA at Home vs. Seeing a Medical Geneticist

At-home WGS tests usually rely on saliva or cheek swabs because they’re easy to collect. In clinical settings, providers may draw blood or use saliva or tissue for high-quality, stable DNA collection. 

At a genetics clinic, a genetic evaluation also occurs before any testing. As a patient, you’ll meet with medical professionals specializing in clinical genetics. Expect a

  • Comprehensive medical, family, and social history
  • Complete physical exam and neurocognitive screen
  • Review of specialty consults, previous tests, and historic diagnoses
  • Evaluation of the most appropriate genetic testing for your needs

A trained genetic counselor will talk with you about how genetics can impact health and family life and your risk for inherited and rare conditions. They’ll help you understand the risks, benefits, alternatives, and limitations of genetic testing for your situation. If you move forward with testing, you’ll be well educated about what to expect and what you might learn.

WGS Testing Accuracy and Clinical Usefulness

For at-home testing, the quality of labs that test DNA samples varies. For the best WGS results, labs should be CLIA-certified (Clinical Laboratory Improvement Amendments) and CAP-accredited (College of American Pathologists). This ensures that the lab follows best practices for achieving reliable results.

Tests also vary in how closely they analyze DNA. The more thoroughly the sample is sequenced, the more accurate your results. For example, you may see numbers like 1X WGS, 30X WGS, and 100X WGS. The higher the number, the higher the accuracy. 30X is usually acceptable for research and general wellness. 100X provides a better chance of finding complex and rare conditions, while reducing the likelihood of false positives or negatives.

Even if the labs used are certified and accredited, doctors will typically not accept the results of at-home tests for diagnosis and treatment. These tests are not FDA-approved for diagnostic use and may not align with the American College of Medical Genetics guidelines.

A clinical genetics practice will always use labs that are CLIA-certified and usually CAP-accredited. They leverage the latest WGS technology, with clinical-grade tests (often with 100X WGS) that offer high sensitivity and specificity. These tests can detect rare, complex, and inherited disorders, with results validated for use by doctors. 

WGS Result Interpretation and Support

At-home WGS tests can provide valuable information about genetic predispositions and risk. The results are worth sharing with your care providers, who may then order clinical tests. Of course, the details in your DNA reports and the support you get from an at-home test depend on what test you order and the plan you pay for. At-home WGS test reports generally include a list of gene variants, risk scores for certain conditions, and information about wellness traits. (More expensive tests may identify or report on a broader variety of diseases and genetic variants.) Result interpretation may be automated, with no expert review, medical guidance, or follow-up, even if something concerning is found. Without this guidance, patients may not fully understand the results or their importance.

If you do testing through a genetics practice, your results will be interpreted by a medical geneticist who knows your personal medical and family history.  The geneticist or genetic counselor will review your results and next steps with you, confirming you understand everything discussed. They’ll also provide counseling, offer follow-up testing, and coordinate with your current doctors, new specialists, and insurance company. Your results may lead to a diagnosis, screening strategies, disease management, and targeted testing of family members.

DNA Data Privacy and Ownership

For at-home tests, privacy may be a concern. Privacy policies vary by company, and some allow third-party use of de-identified data. With many tests, you will own your DNA data, but how it is protected depends on the company. When a clinical practice does testing, your privacy is protected under HIPAA. Data is stored in your secure medical record. It is used only for your care, unless you consent to its use in research.

Insurance Coverage and Cost of WGS

At-home tests range from several hundred to several thousand dollars, depending on the service and level of interpretation. These tests are not covered by insurance, and expert interpretation or genetic counseling may add to the base cost of the test. Clinical genetic testing can be more expensive, but insurance may cover it if ordered by a medical professional. Insurance may require prior authorization or letters of medical necessity, which a genetics practice can help with.

Understanding Your Health and Risk

If you think you’re at risk for a genetic condition, are experiencing unexplained symptoms, or would like to learn more about how genetics can impact your health, talk to your doctor about whether a genetic evaluation would make sense for you. You can learn about SequenceMD and our patient services online, or contact us anytime with questions.