Genetic testing results don't scare consumers but may not result in healthy lifestyle changes either

That's the implication of a study published online this week by The New England Journal of Medicine. It looked at 3,639 healthy consumers who had paid a commercial firm, Navigenics Health Compass, to analyze their genes and report on their lifetime risk of developing 22 different diseases. The study was funded by the National Institutes of Health and the Scripps Genomic Medicine Division of Scripps Health in California. Navigenics didn't provide any financial support for the research, nor were they involved in the study's design.

The researchers tracked anxiety levels in the 2,037 subjects who completed the study. Ninety percent of them had no increase in emotional distress. "When we started, we heard expectations that knowing their genetic risks would put consumers in psychological disarray," said Eric J. Topol, M.D., one of the study's authors and Director of the Scripps Translational Science Institute, in a telephone interview. "Professionals often don't give enough credit to consumers. We found they are much more savvy than anyone would have expected." 

Learning that they were at increased risk of specific diseases seemed to increase people's intention to get additional health screenings, according to the study's authors. This may not translate into more follow-up health screening tests, in part because many of the diseases looked at in the genetic analysis don't have good early-detection screening tests.

Overall, the study showed no evidence of harm from direct-to-consumer testing, but few benefits, too, which may simply reflect the fact that genome testing is still in its toddler-hood. Today's direct-to-consumer genetic tests are "underpowered" with data, according the study authors. They are based on the association of certain genetic markers with people who have a particular disease but, in most cases, the markers account for less than 10 percent of the heritability of the disease studied.

In fact, a previous study found that the same genetic samples were interpreted differently by four different firms. To avoid confusing consumers, Dr. Topol noted that "the industry needs to get its act together and agree on the scientific interpretation of data."

—Ronni Sandroff, Editorial Director, Health & Family