Hypothetical fears have already played out in the United States. The Burlington North Santa Fe railroad company paid $2.2-million to settle a suit after it tried to test employees for their genetic predisposition to carpa tunnel syndrome. A Florida woman sued the employer who fired her after a genetic test showed she carried a rare gene variant that can result in a liver disease.
Last spring, the Chicago Bulls wanted to run a DNA test on basketball player Eddy Curry after finding he had an enlarged heart. Mr. Curry, who refused the test some experts said would be inconclusive, has since been traded to the New York Knicks.
In the United States, insurance companies have agreed to a five-year moratorium on the use of genetic tests. Washington passed a genetic anti-discrimination bill in February, and most states now have legislation on point. But no such law exists in Canada, Prof. Caulfield said.
Dr. Waygood, at the University of Saskatchewan, noted the field also cries out for regulation to protect the consumer against companies offering unreliable information. In 2001, Dr. Waygood was among those who sounded the alarm about a Saskatoon company, Genometrics Corp., which promised fee-for-service genetic testing. The founder of the company, which never did test any patients, was not the expert he claimed to be and has pleaded guilty to several fraud-related charges, including bilking investors.
Still, Dr. Waygood sees the value in genetic testing for preventive purposes. "If it allows you to make lifestyle changes and undergo surveillance, it might be cheaper than having someone occupy an ICU bed for many months later.
"One could be accused of being paternalistic if the view is not to allow access to such information," he said. "In the end, if people want this information they should be able to get it."
A few weeks after his swab, Mr. Zentil received his results from Vienna.
Dr. Chin sat with him for an hour explaining the findings. "I understand these are just associations," he said, "I know there are no guarantees."
The testing revealed Mr. Zentil has a higher than average risk of developing prostate cancer and osteoporosis and a borderline chance of becoming hypertensive.
The higher prostate cancer risk has, as with his known family history of colon cancer, convinced him of the need for regular screening. He has also undergone a bone scan so that he will have a baseline for comparison should his skeleton begin to deteriorate and osteoporosis actually sets in.
But Mr. Zentil also feels he walked away with some good news. He tested negative for one of the gene variants associated with Alzheimer's disease.
"I looked at it. I thought, that's a cool thing," he said, then laughed. "It was a surprise to my wife. . . she thinks I forget a lot of things."
Mr. Zentil understands that genetic information represents a double-edged sword. As an employee, he said he would want the findings to remain private and be judged alone on his ability to perform a job. But as an employer, he admitted, "I'd want to know if someone is going to be a burden on the company health plan."
On his office computer, Mr. Zentil has kept a gag e-mail that recently made the rounds. It's an audio file of a man ordering a pizza in 2010 from a company that has access to all his personal information. It charges him $60 extra for requesting double cheese, telling him it's a risky choice given his high cholesterol levels.
"Now that's scary," he said.