The tired but happy woman reluctantly surrenders her newborn to a nurse, who deftly pricks the infant’s heel with a lancet and squeezes a drop of his blood into an analyzer. Then, as the nurse reads aloud from a printed report, a flush of alarm colors the mother’s face.
“Neurological condition, 60-percent probability,” the nurse’s emotionless voice intones. “Manic depression, 42-percent probability. Attention deficit disorder, 89-percent probability. Heart disorder, 99- percent probability. Early-fatal potential. Life expectancy, 30.2 years.”
That scene has happened only once so far, and it was in a movie: 1997’s Gattaca. The sci-fi flick is set in a world that conducts instant, universal genomic testing.
Today, that scenario is more science than fiction. Thanks to the Human Genome Project, an effort led by the University of Michigan’s Dr. Francis Collins while on leave from that medical center, at least three companies now offer genomic testing directly to the public. While not nearly as comprehensive, swift, or certain as the procedure depicted in Gattaca, such analyses are raising many questions.
Proponents of testing all of a person’s genes — or genome — say the screening will promote early intervention, save money by taking the guesswork out of prescribing drugs, and aid in family planning. But opponents counter by saying it’s far too early to commercialize genomic profiling, because there’s little regulation and much work remains to be done on the science surrounding it. Until then, they say, people who take such tests could be frightened unnecessarily by information they don’t understand, and, as a result, undergo additional, unnecessary tests or procedures.
Still, some eager startup companies are offering genomic profiling on the Internet, including 23andMe, deCODEme, and Navigenics. Today, for between a few hundred and several thousands of dollars, you can swab the inside of your cheek or expectorate into a test tube and send off your sample. They’ll examine your cells for evidence of drug sensitivity, indicators that you’re a carrier of diseases, and your risk levels for an ever-expanding list of chronic or even fatal conditions. Two companies — 23andMe and deCODEme — offer ancestry information.
While these companies mostly have bypassed the medical community and offered their services directly to consumers, Navigenics, of Foster City, Calif., recently redirected its marketing back to doctors and corporate wellness programs. The company altered its promotional efforts after California and New York challenged Navigenics’ practice of offering a medical test directly to the public without a doctor’s orders, a requirement in those states.
The list of issues hardly stops there.
Because the testing occurs outside the confines of regular medicine, the results may not be protected by the federal patient-privacy law, HIPAA. And although a 2008 law, the Genetic Information Nondiscrimination Act, protects people from discrimination by health insurers and employers, it doesn’t apply to life, disability, or long-term care insurance.
Many in medicine say the general public — and even doctors unschooled in genetics — don’t understand the test results and how to best use them. Questions remain about whether some mutations cause a disease or are merely bystanders. How many and which genes are responsible for a disease? How do gene mutations interact? What role does the environment play? Do the results of small studies among Caucasians apply to other races and to large groups? And who oversees these companies?
Worse, studies indicate that a sample from one person sent to several labs sometimes yields different results because the companies don’t agree on the science supporting their testing. Several companies are now voluntarily collaborating to develop uniform standards, however.
Navigenics is working to fill in some of the knowledge gaps, says its CEO, Dr. Vance Vanier. His firm partnered with the Mayo Clinic to research how family doctors can best learn about genetics, and with the Scripps Translational Science Institute, to see if genomic profiling can motivate people to change their lifestyle or better heed medical advice.
“Our focus has always been to partner with the medical community,” Vanier says.
A public-relations representative for 23andMe declined to be interviewed, and deCODEme didn’t respond by deadline. Local genetics experts have mixed feelings, but those interviewed for this article unanimously say it’s too soon to do the kind of testing these companies are promoting.
“In the future, I think this will be a really valuable and powerful tool,” says Dr. Elizabeth Petty, a professor of internal medicine and human genetics and a doctor in the U-M Medical Genetics Clinic. “At present, I don’t think we have enough answers to make broad-spectrum genetic screening clinically useful in most situations.”
Even Collins, who led the Human Genome Project and is now director of the National Institutes of Health, agrees. “The ability to make predictions is still limited by what we don’t know,” he said in a March National Public Radio interview.
Petty recently sent her own sample to Navigenics for testing, an experience she describes as “largely recreational.” But whether that’s a fair description of such testing is another controversy. Eleven states, including Michigan, require a doctor’s order for a medical test. Does calling it “recreational” make it so?
What Petty found out is that she’s at higher risk than the general population for breast cancer and macular degeneration. Her reaction? If she weren’t already visiting an eye doctor regularly for other reasons, she probably would have scheduled an appointment. And her family history and excess weight already pointed to a higher risk for breast cancer, she says.
Despite the lack of answers, genomic testing is filtering down into our culture. The U.S. Food and Drug Administration in 2008 started encouraging health-care professionals to consider pharmacogenomic testing (how a person’s genes affect the way he or she responds to drugs) before prescribing the anti-clotting medicine coumadin and the anti-seizure medication Tegretol. Pharmacogenomic tests have also helped determine hypersensitivity to the HIV drug abacavir. These uses appear promising and do portend the potential for better health and saving money because they eliminate the trial-and-error approach to picking the right drug at the right dose.
Experts predict that five years from now, as technology advances and becomes cheaper, we’ll all have our genomic profile done for about $1,000 to help predict, prevent, and treat inheritable diseases.
Doctors talk excitedly about genomic testing opening the door to personalized medicine and intervention, before a disease is detectable. Knowing one’s risk for Alzheimer’s, Parkinson’s, or other diseases will be useful for planning and preparing the family. Adopted children whose family history is unknown will benefit from knowing their vulnerabilities.
For now, as science works to fill in the genomic gaps, family histories and health questionnaires can tell us much of what we need to know, says Angela Trepanier, a genetics counselor and assistant professor of molecular medicine and genetics at Wayne State University. She’s part of a group advising the government on the scientific foundation for using genomic profiling as a health tool.
For example, she cites a widely used risk assessment for breast cancer that asks five questions related to a woman’s medical history and that of her mother, sisters, and daughters. It can identify 60 percent of the women who are at higher risk. Genomic profiling increases those results by two points, and consumes a lot of medical resources for little gain, Trepanier says.
She and Collins recommend compiling a detailed family history as a highly useful, no-cost way of determining disease risk, until genomic profiling is “ready for prime time.” Several reliable Internet sites have instructions on how to do this.
In the meantime, the government is funding nearly 600 studies nationwide related to genomics. These range from determining which mutations are linked to a particular disease to how best to educate front-line doctors who are not genetics experts.
“Most of them are not trained in it,” says Dr. Barry Wolf, a Henry Ford Hospital genetics expert who answers calls about such testing from area doctors. One of Wolf’s concerns with direct-to-consumer genomic profiling is a patient’s reaction to, say, learning he or she has a debilitating and only partially treatable disease — Huntington’s, for example. It’s an inherited condition that doesn’t show up until adulthood and is characterized by progressive loss of control of muscle movement and mental ability.
“The old way is, we have a person sitting down with a psychologist first to see if he can handle [the news],” Wolf says.
How patients react to the results of genomic profiling also interests Dr. Sharon Alford, another Henry Ford staffer, who led research at the hospital to figure out who is likely to want to get tested. The study provided genomic profiling for eight conditions. It determined that Caucasian women — the same group most likely to seek traditional, narrowly targeted genetic testing — also are interested in genomic profiling’s more wide-ranging approach.
While Alford’s research didn’t address how people would react to the news of their increased risk, she notes that those in the study were not upset. All of the diseases they were tested for are preventable, which may have made a difference. “People seemed to take it really in stride,” she says.
Scientists are also interested in what people will do with their information. Will they be fatalistic, figuring their future is already set, or will they be motivated to take steps to delay or prevent disease onset? Studies so far show that genomic-risk information makes taking drugs for some conditions, such as heart disease and depression, more palatable. However, it has little impact on prompting people to change their lifestyle by, say, quitting smoking or starting exercise.
Alford’s recent research bears this out.
Sandy Hill, of Dearborn, learned through Alford’s study that she’s at higher risk than the general population for heart disease, high cholesterol, colon cancer, type 2 diabetes, and osteoporosis. The 38-year-old loan tech for Comerica Bank says her concern was short-lived.
“That was a little frightening for a few seconds,” she says. “Initially, I was more conscious of it, but it dwindled fast. I don’t think I’m really going to get [any of the diseases].”
A Royal Oak man, whose identity is being protected, was also in Alford’s study. He’s at higher risk for osteoporosis and colon cancer. Despite having two family members who had colon cancer, the 43-year-old said his advancing age is what motivated him to add more fiber to his diet. His yearly physical pushed him to be tested for colorectal cancer.
“Just because the results say you have a higher propensity for this or that, it doesn’t mean you will get it,” he says. “It’s not a death sentence.”
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