Is selling genetic tests directly to consumers a good idea?

Direct-to-consumer sales of genetic tests were rare until November 2007, when three companies began offering them. Since then, tests have been easily available on the Internet, allowing people to send a DNA sample — usually saliva — to companies such as California-based 23andMe and Navigenics and, for a few hundred dollars, get back information about their genetic ancestry and medical risks. [Footnote 11]

DTC vendors say the tests help curious people learn about themselves and that their analyses are based on the best current scientific understanding. Critics, however, contend the science of genetic testing isn't far enough along to yield meaningful results.

“Customers empowered with this information have made lifestyle changes aimed at reducing their risks of developing disease and have provided information to their doctors to aid in diagnosis and treatment. These actions have improved and even saved lives,” 23andMe general counsel Ashley C. Gould told a House oversight committee last July. [Footnote 12]

While saying she could not speak for the whole industry, Gould said her firm provides “extensive information to our customers so they understand that the data we provide can change as new scientific studies are completed.” [Footnote 13]

Purchasers of DNA health-risk profiles are mainly well-off, technically savvy people, so it's not clear how far one can generalize from their response to DTC testing, said David Kaufman, director of research and statistics at the Genetics & Public Policy Center, a research and survey group jointly sponsored by the Pew Charitable Trusts and Johns Hopkins University. Nevertheless, current customers' self-reported responses to test results suggest testing's potential in preventive health, he said. [Footnote 14]

Asked whether they'd made health-related lifestyle changes after DTC tests informed them they had medical risks, 34 percent of people surveyed by the center said they were more careful about what they ate, 14 percent said they exercised more and 16 percent had changed their medications or dietary supplements. “We don't give enough credit to people's abilities to decide what's useful to them,” said Kaufman. [Footnote 15]

But Congress' nonpartisan auditing and investigative arm, the Government Accountability Office (GAO), blasted current DTC tests in a report last July. After buying tests from four websites, GAO analysts created biographical profiles of several “fictitious consumers” of various ages, weights and lifestyle descriptions and submitted them along with DNA samples taken from only one woman and one man. Although the DNA came from just two people, the companies sent back a wide and bewildering variety of risk profiles and recommendations, the GAO said. [Footnote 16]

“Although there are numerous disclaimers indicating that the tests are not intended to diagnose disease, all 14 results predict that the fictitious consumers are at risk for developing” conditions ranging from osteoporosis to cancer, presumably based on lifestyle profiles, not DNA, said Gregory Kutz, GAO managing director for forensic audits and special investigations. “If the recommendations were truly based on genetic analysis,” then all the fictitious females “should have received the same recommendations because their DNA came from the same source. Instead, they received a variety of different recommendations, depending on their fictitious lifestyles.” [Footnote 17]

“Test results can be unreliable and difficult to interpret, and they are often offered to people with little or no genetic counseling or support,” said Christopher Hood, of the Nuffield Council on Bioethics in London. “People should be aware that other than prompting obvious healthy lifestyle choices such as taking more exercise, eating a balanced diet and reducing alcohol consumption, the tests are unlikely to inform them of any specific disease risks that can be significantly changed by their behavior,” said Hood, chairman of the council's Working Group on bioethics and Gladstone professor of government at All Souls College, University of Oxford. [Footnote 18]

“With only a few exceptions, what the genomics companies are doing right now is recreational genomics,” said David B. Goldstein, a professor of molecular genetics and microbiology at Duke University. [Footnote 19]

Having access to one's own sequenced genome, once that becomes feasible and affordable for everyone, won't add much to most people's understanding of their health risks, says Barbara Bernhardt, a genetic counselor and clinical professor of medicine at the Hospital of the University of Pennsylvania. “You're going to find every single difference in your genome from what may be considered normal. But you won't have a clue about what that means,” nor will anyone, including scientists, she says.

“Even highly educated people misinterpret test results,” says Kaufman of the Genetics and Public Policy Center. For example, told that a DTC test found a hypothetical woman having a risk of diabetes that was lower than the general population's risk, 7 percent of people, most of them fairly well-educated, erroneously concluded that the woman actually was at high risk of the disease.

“People were more likely to misinterpret a low-risk number” as predicting a high risk, Kaufman says. This might happen “because people are just looking for high-risk information,” he suggests.

Timothy Caulfield, a professor of law and public health at the University of Alberta, one of Canada's largest research institutions, said that in one study, a whopping 78 percent of people who said they are interested in being tested also said they “would ask their physician for assistance with interpreting the data. Further, 61 percent of respondents felt that physicians have a professional obligation to help with this interpretive process,” he said. [Footnote 20]

However, “the data is of only marginal health benefit,” according to most analyses, meaning that the costs and time used up in those physician visits would provide “little or no health benefit” to anyone, Caulfield said. Cash-strapped health-care systems can ill afford such luxuries, he said. [Footnote 21]

In addition, hopes by some that genetic testing will eventually hold down costs by dissuading doctors and patients from using medical treatments that gene tests show won't work for them are probably overly optimistic, genetics counselor Bernhardt speculates.

Diseases once thought to be single conditions are now known to have quite different genetic origins in different individuals. As a result, scientists already know that people with certain genetic profiles simply won't benefit from some therapies. And such findings will certainly proliferate, Bernhardt says. But even if testing definitively demonstrates that a patient won't benefit from a given therapy, physicians will most likely prescribe it anyway, since “no one will do nothing” for a sick patient, she says.

The Issues:
* Are effective therapies derived from gene science on the horizon?
* Is selling genetic tests directly to consumers a good idea?
* Should the government award patents for “naturally occurring” genes?

For more information on the CQ Researcher report on "Genes and Health" [subscription required] or purchase the PDF.

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Footnotes

[11] For background, see Jordan P. Lerner-Ellis, J. David Ellis and Robert Green, “Direct-to-consumer Genetic Testing: What's the Prognosis?” Council for Responsible Genetics website, www.councilforresponsiblegenetics.org.

[12] Testimony before the House Energy and Commerce Subcommittee on Oversight and Investigations, July 22, 2010, http://energycommerce.house.gov.

[13] Ibid.

[14] Quoted in “Personal Genomics Tests Prompt Lifestyle Changes,” New Scientist online, Nov. 5, 2010, www.newscientist.com.

[15] Quoted in ibid.

[16] Testimony before House Energy and Commerce Subcommittee, op. cit.

[17] Ibid.

[18] Quoted in Ben Richmond, “Direct to Consumer Genetics Testing Kits Aren't Worth Spit, According to British Study,” Medill Reports, Northwestern University Medill School of Journalism, Oct. 20, 2010, http://news.medill.northwestern.edu/chicago/news.aspx?id=170660.

[19] Quoted in Nicholas Wade, “Genes Show Limited Value in Predicting Diseases,” The New York Times, April 16, 2009, p. A1.

[20] Timothy Caulfield, “Direct-to-consumer Genetics and Health Policy: A Worst-Case Scenario,” The American Journal of Bioethics, June-July 2009, p. 48.

[21] Ibid.