Conference: Genome sequencing opening door to personalized medicine

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Speaking at the 2007 Frontiers of Health Care Conference at Brown University in Providence, R.I., yesterday, Francis S. Collins, MD, PhD, director of the National Human Genome Research Institute, said advances in genetic testing means that “discovery rockets forward.”

The organization has had the goal of sequencing a person’s genome for a cost of no more than $1,000. Currently, it costs about $1 million and will probably drop to about $100,000 within the next year, Collins said. That reduction will help researchers and clinicians identify flaws in everyone’s DNA and determine which conditions pose a greater risk to a specific individual.

Genetic factors in such conditions as diabetes, heart disease and mental illness determine who will suffer from these problems and how severely. Major risk factors for some conditions will be identified in the next 2 to 3 years—some even this year. “This is a remarkable opportunity,” Collins said.

More widespread use of genetic testing raises numerous questions, such as: how to administer appropriate oversight; how to ensure equitable access; and how to reimburse for preventive medicine. If the testing must be paid for out-of-pocket by patients, few will undergo the procedure, Collins said. And for those who are tested, who is going to help them sort through the results? “Are practitioners ready to become genetic counselors,” he queried. He said that the American Medical Association, American Nursing Association and the Genome Project have jointly created the National Coalition for Health Professional Education in Genetics to create and disseminate educational tools for providers.
By studying flaws in the 1 percent of a genome sequence that affect a patient’s health and risk of disease, physicians can learn more about disease, as well as determine which medications are best suited for which patients. For example, “diabetes is a geneticist’s nightmare,” Collins said. “It’s been very tough to unravel.” Researchers knew about three genes that play a role in determining who will suffer from the condition, but three recent studies that looked at the entire DNA genome turned up several more. “This approach is breaking things wide open,” he said. Meanwhile, pharmacogenomics will play a bigger and bigger role in personalized medicine. An individual’s genome sequence can help determine who will react best or poorly to certain medications. For example, Abacavir is a drug for HIV that can be very effective for about 95 percent of the population. About 5 percent, however, are hypersensitive to it. Prescreening can determine who be sensitive and eliminate trial and error processes to find an effective medication.

Despite the promise of genomics, progress is stymied by our reimbursement system. Rep. Patrick J. Kennedy (D-RI), co-sponsor of the conference, said that we need to rearrange incentives to shift to a public health and primary care approach to healthcare. “Genetic testing is not enough,” he said. He cited studies that show that traumatic childhood experiences result in a higher probability of intravenous drug use, suicide and HIV. Foster care makes up 3 percent of the population but 40 percent of the juvenile justice population.

Another important part of the genetic testing process is learning more about how people react to this kind of information, Collins said. The “multiplex” project is looking at 1,000 people who have been genetically tested for six different diseases and then watching them for the next year. Do they understand the full complexity of the information? Will they do anything differently?

Daniel J. Wattendorf, MD, family physician and clinical geneticist at the Keesler Air Force Base and the National Human Genome Research Institute, participated in a panel discussion. He said that electronic medical records offer a tremendous opportunity to track data. He cited the example of high blood pressure—5 to 10 percent of patients have high blood pressure as a secondary condition while the other 90 to 95 percent have it as a primary condition with no known cause. “Data can be put into an algorithm and all the other pieces put into place,” he said. Without using computers to track data, “you’re just acting on experience” to treat patients.

“Attention to ethical, legal and social issues is more important now than ever,” said Collins. Steps have been taken, with the House passing a bill on genetic discrimination on April 25, 2007 by a vote of 420-3. Although laws against