Regardless of the differences between the studies, the fundamental findings are the same, both McPherson and Stefansson stress.

The researchers anticipate that the identification of the variant will lead to new DNA-based diagnostic tests that could identify young people at high risk for heart disease. With a new test, physicians could potentially select the high-risk patients who would benefit most from lifestyle changes and drugs like aspirin, statins, and the like. This is a disease for which there are "good preventive therapies," says McPherson.

The newly identified genetic risk variant is not actually a gene; rather, it's a segment of DNA that falls in the vicinity of two genes previously implicated in cancer. "Our experience is that almost all these variants that predispose to the common diseases are not in the coding sequence of genes," says Stefansson. "They are outside the coding sequence and influence expression. I'm not surprised to find them some distance away from genes."

In just the past week, the location of the risk variant has become a hot spot in the genome. Four independent teams, including DeCode, published reports linking the same region on chromosome 9 to diabetes.

"I think this is a stunner," says Francis Collins, director of the National Human Genome Research Institute, in Bethesda, MD, and leader of one of the four teams, during a seminar on genome-wide association studies. "This is like the seat of the soul of the genome. It seems like this one place carries all of that weight for two very common and very dangerous diseases."