Commentary

DTC genetic health risk tests: Beware

Publish date: April 21, 2017
By
Elena M. Stoffel, MD, MPH

 

The Food and Drug Administration recently authorized 23andMe to provide consumers with results of germline DNA sequence variants associated with risk for 10 health conditions, among them hereditary hemochromatosis, alpha-1 antitrypsin deficiency, celiac disease, Alzheimer’s disease, and Parkinson’s disease. After they submit a saliva sample and pay a test fee, customers ordering the online test will receive a report delineating their ancestry markers and informing them whether they carry any of the genetic variants associated with selected health risks included on the targeted DNA sequencing panel.

Dr. Elena M. Stoffel of the University of Michigan, Ann Arbor

Dr. Elena M. Stoffel

The FDA initially had issued a warning to 23andMe preventing them from including information about health risks on these direct-to-consumer (DTC) test reports. However, the current DTC test appears to meet the FDA’s requirements for test accuracy and reproducibility. Yet, it is important to note that the FDA’s authorization is not an endorsement of the validity or clinical utility of DTC health risk tests, which simply analyze whether an individual’s DNA carries a genetic variant associated with “increased” risk for the condition in question. In fact, the American College of Medical Genetics warns that DTC genetic tests, which interpret genomic information in the absence of individuals’ clinical and family history, have the potential to be misleading for both clinicians and patients, resulting in unnecessary worry and/or additional testing. When examining results of DTC health risk tests, the following truths should be self-evident: First, being a carrier of a genetic marker associated with a disease does not mean that a person has the disease or will necessarily ever develop the disease. Second, a negative DTC genetic test result does not exclude the disease.

As more consumers partake in “recreational genomic testing,” clinicians should understand the limitations of DTC genetic tests and should be prepared to discuss with patients why these should not supersede clinical diagnostic evaluations.

Dr. Stoffel is a gastroenterologist, assistant professor of internal medicine, and director of the cancer genetics clinic at the University of Michigan, Ann Arbor. She has no disclosures.

Recommended Reading

Sigma-1 agonist presses forward after positive results in small Alzheimer’s trial
MDedge Internal Medicine
Phase I results move Alzheimer’s candidate drug aducanumab into phase III trials
MDedge Internal Medicine
Ladostigil advances to phase III after hints of slowing brain atrophy in MCI patients
MDedge Internal Medicine
Early mild cognitive impairment in Parkinson’s leads to dementia in more than 40%
MDedge Internal Medicine
Proposed Alzheimer’s classification system relies solely on biomarkers
MDedge Internal Medicine
Testosterone Trials’ cardiac, cognitive results disappoint
MDedge Internal Medicine
Mid-life cardiovascular risk factors set stage for later-life dementia
MDedge Internal Medicine
Hemorrhagic stroke increases risk of depression and subsequent dementia
MDedge Internal Medicine
Evolocumab doesn’t make patients dumb
MDedge Internal Medicine
Hard road disproving that statins make you dumb
MDedge Internal Medicine

Related Articles