What Effect Does Gene-Screening Have?

With new genetic testing available, researchers can calculate whether you have an increased risk for diabetes, breast cancer and heart disease, among other illnesses.

But now the National Institutes of Health wants to find out whether it actually make any difference to someone who learns their risks.

NIH researchers are starting to see results from the Multiplex Initiative, a project designed to answer that and other quandaries about genetic testing.

While final results are a few months away, researchers say the initial signs are encouraging. People seem to be taking their genetic information in stride, according to Lawrence Brody, a senior investigator at the National Human Genome Research Institute and one of the researchers on the study.

"These genetic things are not their destiny, just a guide," he told ABC News.

In the spring of 2006, Brody and other NIH researchers partnered with doctors at the Henry Ford Hospital in Detroit to see whether people would pursue genetic screening to find out more about their DNA, how they would interpret the information they received, and what kind of medical advice they would seek once they had that information.

"We'll learn a lot about whether they thought [a genetic screening] was a good idea, whether they were sorry, and whether or not they understood the test results," Brody told members of the media assembled at the Jackson Laboratory.

So far, Brody said, patients who opted to get genetic information have been following up on it, and there have not been widespread incidents of people taking news of genetic susceptibilities harshly.

But Brody emphasized that the current pilot program is just a first step, and will not be able to say on its own whether these genetics screenings lead to better overall health.

"As a genetic counselor, I feel this type of research is really critical," said Jill Stopfer, a certified genetics counselor at the University of Pennsylvania's Abramson Cancer Center. "We need to know what to do with this information, we need to know how to deliver this information."

Many geneticists are worried how patients will interpret their susceptibilities for various diseases. Brody cited the number of genes associated with breast cancer as an example of the difficulty of such interpretations. While some genes -- such as the widely-known breast cancer genes BRCA1 and BRCA2 -- can increase risk by up to 85 percent, Brody cited a number of other genes that have shown only a very slight increase in the risks of breast cancer.

That lack of knowledge has led to concerns about the growth of direct-to-consumer testing, where companies offer to decode your genome and send you the results.

Counselors like Stopfer worry about how people will interpret the results they get from such tests, since they typically do not include the counseling that would accompany it in a clinical setting.

"It's not that they're hurling themselves off bridges, but they're making inappropriate medical decisions," said Stopfer, citing patients who undergo unnecessary operations to ward off cancers they have only a minor risk of ever contracting.

"It's hard stuff to get, and we have to get it across in a way that it is understandable and actually motivates people," said Brody.

For that reason, he said, much of the information distributed to patients has to be very carefully worded so that not only lay people, but doctors without a firm knowledge of genetics, would be able to understand it.

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