Gene Mapping for Healthy People No 'Crystal Ball'
Mapping Fails to Predict Most Diseases: Study
Gene Mapping Not Always Informative continued...
In the case of Alzheimer's disease, for example, the research suggests that a whole-genome map would identify most people with at least a 10% lifetime risk of developing the disease. Still, "a 10% risk for disease does not imply that this disease will be his or her major health problem," Vogelstein cautions.
What limits the usefulness of genes to predict disease? Contrary to what most people think, environment plays only a small role in changing your genes, Vogelstein says. "Much more important are random mistakes in genes that occur when cells divide," a process that starts in the womb, but can also occur anytime throughout life, he says.
Whole Genome Testing: Experts Comment
The key to fighting cancer and other disease remains routine checkups, early screening tests, and a healthy lifestyle that includes not smoking and maintaining your ideal weight, among other strategies, Vogelstein says.
Timothy Rebbeck, PhD, of the University of Pennsylvania Perelman School of Medicine in Philadelphia, notes that the current findings only apply to healthy people, and that gene mapping can be beneficial for identifying inherited illnesses or for finding the best treatments for people who are already sick.
"For someone who has disease, whole-genome sequencing can be extremely valuable," he says.
Louis M. Weiner, MD, director of the Georgetown Lombardi Comprehensive Cancer Center in Washington, D.C., says that the study offers "a cautionary tale not to rush into using new technology" until its benefits and limitations are understood.
Whole-genome testing, which cost several hundred thousand dollars only a few years ago, can now be performed for $1,000 to $3,000, though it varies form company to company.
Vogelstein receives royalties on sales of technologies or products related to the study.