SYDNEY -- A team of Australian scientists has discovered a new gene that could save lives by helping doctors identify patients vulnerable to heart attack or stroke.

People who have high levels of a protein produced by the gene have as much risk of suffering a heart attack or stroke as those with high levels of cholesterol or high blood pressure.

Dr Sam Breit, of the Center for Immunology at St Vincent's Hospital in Sydney, told reporters the discovery of macrophage inhibitory cytokine-1, or MIC-1, could pave the way for routine tests in about two years.

"Your risk of having a heart attack or stroke from having an elevated MIC-1 is approximately the same as having an elevated cholesterol or having elevated blood pressure," he said.

A blood test for MIC-1 levels, along with other tests, could form part of a predictive program.

"It's one more test that's as important as cholesterol measurement and as important as CRP (another protein associated with heart attack risk) measurement." Breit and his research team discovered and cloned MIC-1 in 1997.

But it is only recently that a collaborative study between him and the United States' Harvard University established a link between MIC-1 and an inflammatory disease of the arteries - atherosclerosis - that can lead to heart attack or stroke.

The study, published in the British medical journal **** The Lancet **** this week, took blood samples from 27,600 women and followed them over four years.

It found patients who had a heart attack or stroke had higher levels of MIC-1 in their blood than those who did not.

"We are now more easily able to identify a group who are more prone to heart attack and stroke," he said.

"With these new molecular markers we will be able to more easily identify patients at high risk so that they can be managed with greater preventative measures such as lifestyle and diet changes together with more aggressive drug therapy." The study shows that people with high MIC-1 levels are up to two-and-a-half times more prone to heart attack or stroke.

Patients with high levels of CRP, or C-reactive protein, as well as elevated MIC-1 face up to four-and-a-half times the risk.

Each time an additional lifestyle factor like weight, cholesterol, smoking or blood pressure was added to the equation the risk multiplied threefold, AFP quoted Breit as saying.