Genetic testing has made it possible to determine, using a sample of saliva, if a person has a higher- or lower-than-average risk of developing Alzheimer's disease. But, given the opportunity to find out, how many people would actually want to know?

Julian Awad, CEO and co-founder of Smart Genetics (Philadelphia), a company that has developed an at-home test kit called Alzheimer's Mirror to test for APOE, a gene linked to late-onset Alzheimer's, says the test is not for everybody.

"When our team went out and polled over 100 families there were just people that do not want to know this information, and that's okay," Awad told Diagnostics & Imaging Week. "And there are people who think, 'Why in the heck would you not want to know?'"

If you posed the question at a cocktail party, the room would most likely be split with half the people wanting to know and the other half not wanting to know, he said.

Awad, of course, falls into the first group. He not only wanted to know, but chose to find out the results of his test publicly last month on CBS Evening News with Katie Couric.

Here's how the test works: Everyone is born with two copies of the APOE gene, one from their mother and one from their father. The gene comes in three components: E2, E3 and E4, which means there are six possible combinations that a person can carry. While the general population has about a 10% to 15% chance of developing Alzheimer's, a person's APOE genetic status can alter the risk, as can non-genetic factors such as family history, age, gender, and ethnicity (women are more likely to develop the disease than men, and African Americans also are at a higher risk for the disease).

Awad's APOE genetic status, for example, is E2-E3, meaning his lifetime risk of developing Alzheimer's is lower than average. He also has some non-genetic factors in his favor he is a male Caucasian but his family history of the disease also is a factor. If he were among the roughly 2% of the population whose APOE status is E4-E4 his lifetime risk for developing Alzheimer's would be considered "much higher than average."

Awad believes that knowing this information ahead of time is beneficial because it gives people a chance to prepare by talking to their families about how they would like to be cared for if they do develop the disease. It also may encourage consumers to lead a healthier lifestyle through diet and exercise with the hope that it might reduce their risk.

"It empowers them with the information, it empowers them with what to do next," Awad said.

The good news for consumers who do decide to find out their genetic likelihood of developing Alzheimer's or a number of other conditions that genetic testing companies offer is that they are now legally protected from being discriminated against based on the results. President George Bush signed a bill into law in May that prohibits employers from denying employment, promotions, or health coverage to an individual even if their genetic testing shows they may have a predisposition toward an illness such as cancer or heart disease. The new law also prevents insurance companies from using the genetic information to determine premiums or eligibility.

— Amanda Pedersen