After paying hundreds of dollars for direct-to-consumer genetic testing (DTC-GT), people need someone they trust to explain what the results actually mean. Many turn to their physicians.

“The problem for clinicians is that they do not know what kind of lab did the test or how reliable it is,” says Kenneth W. Goodman, PhD, FACMI, FACE, professor and director of the Institute for Bioethics and Health Policy at University of Miami’s (FL) Miller School of Medicine.

The results often are not clinically informative. Patients might interpret it in a way that makes them worry when they should not, or not worry when they should. “This is why credible genetic testing includes the service of genetics counselors,” Goodman observes. As for DTC-GT, Goodman says, “clinicians should make clear that many of these tests are more like parlor games than medical assessments.”

The added question of who is using the consumer’s genetic testing data, and for what purpose, also is ethically concerning. “If a patient is curious about DTC, it should be with eyes wide open, not wide-eyed,” Goodman suggests.

Researchers recently surveyed 1,502 primary care and specialist physicians to learn how often patients were bringing in DTC-GT results. Thirty-five percent of primary care physicians and 12% of specialist physicians had received at least one from a patient in the past year.1

A previous study concerned how well customers of DTC-GT understood their results.2 “In that study, and others that have looked at the topic, we found that for the most part, interpretation of test results from DTC-GT is fairly good,” says Scott McGrath, PhD, a clinical informatics education specialist at Providence Health & Services in Renton, WA.

Customers correctly interpreted the tests about 75% of the time. “But what was surprising was that the people we looked at were highly educated and above average means,” McGrath says.

The mean income in the study was more than $90,000. “The study was done when the tests were largely a novelty,” McGrath notes.

Investigators expected that as more people purchased the testing, medical professionals would be fielding questions about the results. “One of the problems with that model is that there is a shortage of genetic specialists in the medical field,” McGrath reports.

Therefore, primary care providers would be the ones hearing the questions. “We wanted to look at what primary care providers thought about that,” McGrath says.

Researchers were interested in how the primary care doctors rated their own ability in interpreting genetic test results. When asked to evaluate their comfort levels, the primary care doctors doubted their confidence to a greater extent compared to genetic counselors.

Researchers also studied how the primary care doctors’ ability to correctly interpret the tests compared to genetic specialists. These specialists interpreted DTC-GT results correctly 83% of the time, but primary care providers did so 74% of the time.3 “It was reassuring that there wasn’t a huge gap in the ability to properly interpret these results between primary care providers and the specialists,” McGrath says.

However, the two groups of physicians differed much more in another aspect. Primary care doctors were more likely to trust the results returned from DTC-GT. Genetic specialists were more skeptical. “Some of these tests may not be as rock-solid as they would be comfortable with when advising patients,” McGrath offers.

One genetic counselor put it this way: “If you are asking whether I think the data is accurate, the answer is generally yes. But if you were asking do I think the descriptions and recommendations are comprehensive, the answer is no.”

Several genetic counselors expressed a wish to explore the results more. One commented, “It is alarming how much information the DTC reports give without giving any sort of context of the nuances that go into interpreting results.”

Genetic specialists clearly remain the “gold standard” when it comes to interpreting genetic test results. However, the study’s findings suggest primary providers are a reasonable option, too. “The overall primary care providers can step in to provide assistance in interpreting these tests if there is high demand,” McGrath says.

One ethical concern is whether genetic data should be included in medical records if there is a risk it is going to be misinterpreted by a medical professional without specific expertise. The findings alleviate this concern somewhat, since it shows that medical professionals who are not domain experts interpret the results reasonably well.

“But it also shows the benefits of having more experts, genetic counselors, and clinical geneticists, given the rapidly developing environment of genetic and genomic research,” McGrath adds.

REFERENCES

  1. McGrath SP, Coleman J, Najjar L, et al. Comprehension and data-sharing behavior of direct-to-consumer genetic test customers. Public Health Genomics 2016;19:116-124.
  2. McGrath SP, Walton N, Williams MS, et al. Are providers prepared for genomic medicine: Interpretation of direct-to-consumer genetic testing (DTC-GT) results and genetic self-efficacy by medical professionals. BMC Health Serv Res 2019;19:844.
  3. Jonas MC, Suwannarat P, Burnett-Hartman A, et al. Physician experience with direct-to-consumer genetic testing in Kaiser Permanente. J Pers Med 2019;9.