Even as the Obama administration scrambles to find new ways to rein in health-care costs, a new trend in consumer medicine might boost unnecessary spending.

A number of direct-to-consumer companies now offer genetic testing over the Internet, providing customers with estimates of their risk of developing different diseases and other information. Many people then take these reports to their physicians, "who have little idea of how to interpret them, let alone how to act on them," says Michael Murray, a medical geneticist at Brigham and Women's Hospital, in Boston. "No one has a handle on the economic cost to health care."

Over the long term, geneticists and physicians hope that genetic testing for disease risk will reduce health-care costs by enabling targeted early screening and better preventative medicine. But in the near term, as clinicians and scientists learn how to use genetic information, the results of direct-to-consumer tests might prompt physicians to order screening tests and other procedures that they likely would not do otherwise. "We don't have the foggiest idea whether this is generating a ton of downstream cost," says Murray, who discussed the issue at the Consumer Genetics Conference in Boston last week. "My hunch is, if not now, it probably will."

Murray hopes to have a more concrete answer soon. He is surveying health-care providers who have received these types of inquiries from patients to find out what questions patients ask and whether follow-up tests were ordered based on the results.