A major study by leading research groups published on Wednesday independently identified mutations in a single gene that protect against heart attacks by keeping levels of triglycerides — a kind of fat in the blood — very low for a lifetime.
These findings are expected to lead to a push to develop drugs that mimic the effect of the mutations, potentially offering the first new class of drugs to combat heart disease in decades, experts say. Statins, which reduce LDL cholesterol, another cause of heart disease, became blockbusters in the late 1980s. Since then there have been no major new drugs approved for lowering heart disease risk. But experts caution that drug development takes years and that there are no guarantees that new treatments will work as hoped.
Heart attacks are the leading killer in the United States, and about 720,000 Americans a year have them.
Although statins are effective in reducing heart attack risk, many users still often have high levels of triglycerides and go on to have heart attacks.
“We’ve been looking for something beyond statins,” Rader said. “After we have put people on high-dose statins, what else can we do? Essentially nothing.”
The discovery announced on Wednesday was hinted at in 2008 in a much smaller study in the Amish conducted by researchers from the University of Maryland’s medical school. One in 20 Amish people has a mutation that destroys a gene, APOC3, involved in triglyceride metabolism, as compared with one in 150 Americans generally. The scientists were intrigued but did not have enough data to nail down the gene’s role in heart attacks.
Sam, a 55-year-old Amish farmer who declined to have his last name published, saying he was uncomfortable about being conspicuous, has such a beneficial mutation. He recalls little heart disease in his family.
“Those who carry the gene mutations have a 40 per cent reduction in triglyceride levels and a 40 per cent lower risk of heart disease,” said Dr Sekar Kathiresan of Massachusetts General Hospital and the Broad Institute. He is the lead researcher on the gene project.
Now, he added, “there is a route to heart attacks that is independent of LDL,” referring to the form of cholesterol associated with heart disease.