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.
"The medical community is not set up for this," said Brody.
Additionally, Brody said, there was a need to make sure that even basic health advice was written differently to people with certain genes.
The concern, he explained, was that a patient with a slight genetic susceptibility for heart disease and a patient without that risk should both exercise and avoid unhealthy eating, but if given the same advice, they might not understand the purpose of genetic testing and choose to ignore their results altogether.
For many other genetic susceptibilities though, Brody expects the study to take a closer look at what tests are used and whether certain people really have to undergo those screenings.
Brody also gave the example of Jeff Gulcher, the chief scientific officer for the genetic diagnostic company deCODE, who underwent genetic screening and learned that he was at risk for prostate cancer.
Gulcher promptly underwent a screening for prostate cancer. And even though, in his late 40s, he was not old enough for screening to be routinely recommended, the disease had progressed to the point where he may have died before reaching the recommended screening age of 50.
"Potentially that was a good thing, but when you go forward, you have to decide whether society's going to pay for it, and is this really a good thing?" said Brody.
Clearly some believe that it's not. While many see gene testing as a positive, a significant number of patients choose not to undergo genetic testing. One other goal of the Multiplex Initiative is to figure out who does and does not want to undergo these tests.
"We will know what, if you ask 2,000 people if they're interested in this, what the demographics and characteristics are of the people who say yes," said Brody.
Thus far, genetic testing has focused largely on diseases where steps can be taken to avoid them. But even then, some people would rather avoid having even those risks hanging over their heads.
"There are absolutely people who don't want to know. They want to take their chances," said Stopfer.
That choice, ultimately, is left up to the individual.
"People need to look it in the eye and decide: Is it worth living with the knowledge," said Stopfer, "or is it better to leave it lie?"