Home DNA tests: Dubious precision beyond their perceived reliability
Tossed up tales echoing in your head? You know the ones - the craze about taking a DNA test at home to learn more about your health.
From young mothers grappling with the risk of Alzheimer's disease, to guys thinking they've had celiac disease all along, or ladies figuring out the mystery behind their lifelong ailments, the scenario may seem different, but the sales pitch remains the same: Buy a test online, take it in your cozy abode, and gain insights about yourself and your health.
It's a promising premise swept up in an avalanche of marketing, and it's proving to be profitable. The home DIY genetic and health testing business is now a whopping multimillion-dollar industry. By 2017, more than 12 million people had dipped their toes in this trend, purchasing kits for as low as $200.
But are these tests as accurate and helpful as they're made out to be? Let's delve deeper.
"As a general rule, no, these tests are not effective," says Fuki Hisama, M.D., medical director at University of Washington Medical Center's Genetic Medicine Clinic, "In fact, they can be downright harmful."
Hisama sees patients who've relied on these tests, misunderstood the results, misinterpreted the data, and misdiagnosed themselves with conditions they don't have. So, are these tests just another fad or a dangerous gamble?
Robin Bennett, M.S., L.G.C., a senior genetic counselor at UW Medical Center's Genetic Medicine Clinic, echoes Hisama's sentiments. "These tests should ideally be approached as fun and interesting, nothing more," she advises.
Health authorities, like the Centers for Disease Control and Prevention, also caution against taking these consumer tests too seriously when it comes to health concerns. So what's the concern here? Well, let's break it down.
Direct-to-consumer health and genetic tests explained
These home DNA kits serve multiple purposes, ranging from genealogy discoveries to genetic health tests that scan for gene variants linked to diseases like breast cancer, Alzheimer's, or Parkinson's. The process usually involves spitting into a plastic test tube, posting it back to the company, and waiting a few weeks for your results. The report will list any genetic risks, general health information, as well as some entertaining tidbits like whether you're more likely to hate cilantro or be afraid of heights.
For wellness tests, blood or urine samples are typically analyzed to detect a host of issues ranging from food sensitivities to hormone and cholesterol levels. Now you're wondering, "Why all the negativity from the experts?"
The science behind the scrutiny
"These tests are not health tests, because they haven't undergone the same comprehensive laboratory analysis as those ordered by your doctor," explains Bennett.
Home health tests generally only scan for a limited number of gene variants among thousands of possibilities. Worse yet, some companies employ questionable medical testing methods.
For instance, a recent Los Angeles Times article shared the story of a breast cancer survivor who tested negative for a gene mutation after taking a home DNA test.
Misinterpretations caused by these tests can lead patients to forgo professional genetic counseling or medical care they desperately need. On the flip side, a study showed that a staggering 40 percent of variants reported in raw DNA data from direct-to-consumer genetic tests turned out to be false positives upon retesting in a clinical lab, resulting in unnecessary worry and stress for the patients.
"These tests feed anxiety, making it tough for healthcare professionals to reassure patients with incorrect results," says Bennett.
Another issue lies in the massive disconnect in the testing methods for home kits and lab-ordered tests. In-clinic tests take into account your entire medical history, family history, and relevant factors to offer an accurate diagnosis and tailor-fitted treatment plans.
Moving forward
While there are home tests you can take without reservations, like pregnancy tests and evidence-based genetic studies for ovarian cancer risk, the jury's still out on the accuracy and usefulness of direct-mail tests for diseases like breast cancer, Alzheimer's, and Parkinson's.
Even with discreet, convenient, and affordable at-home STI testing, getting tested at a clinic still offers significant advantages. The treatment process can be expedited, and if consumer tests come back positive, you'll need to consult a doctor for validation and medication anyway.
Lastly, keep in mind, as Hisama advises, "If you're thinking about making a diagnosis or decision about medical treatment, please see a doctor or qualified healthcare provider." In other words, save the home DNA tests for fancy genealogy family reunions and stick to professional healthcare for your health concerns.
- Despite the appeal of learning about Alzheimer's disease and other chronic diseases through direct-to-consumer health and genetic tests, medical experts warn against their accuracy and potential harm.
- The marketing surrounding these tests, which claim to analyze genes linked to conditions like Alzheimer's, breast cancer, and Parkinson's, is profitable, but the tests themselves have not undergone the same comprehensive laboratory analysis as those ordered by doctors.
- Robin Bennett, a senior genetic counselor at the University of Washington Medical Center's Genetic Medicine Clinic, suggests approaching such tests as fun and interesting, but not as a reliable source for medical diagnosis or treatment decisions.
- The Centers for Disease Control and Prevention also cautions against taking these tests too seriously when it comes to health concerns, as misinterpretations can lead patients to forego professional genetic counseling or medical care they may desperately need.
- Advocates for mental health and neurological disorders like Alzheimer's argue that home DNA tests feed anxiety and can make it difficult for healthcare professionals to reassure patients with incorrect results, emphasizing the importance of seeking professional help when dealing with such conditions.
