For the first time, scientists have identified a gene turned on by fatty food. Researchers say the gene, found in both mice and humans, conclusively links high-fat diets to heart disease.
Each year, hundreds of thousands of people in the United States alone are diagnosed with hardening of the arteries. The condition, called atherosclerosis, leads to heart disease--the major cause of death in the Western world. A fat-rich diet is clearly responsible. But even though researchers have linked 11 genes to heart disease, the mechanics of atherosclerosis remain largely unknown.
Geneticist Xiaosong Wang of Jackson Laboratory, in Bar Harbor, Maine, and his colleagues at the Karolinska Institute in Sweden focused on three of the suspect genes. They found that when they expressed high levels of a gene called Tnfsf4 in mice fed a high-fat diet (which closely resembles that of the average American), the animals experienced a significant increase in the severity of atherosclerosis. When the researchers "knocked out" the gene, the size of fatty substances in the arteries decreased remarkably.
The researchers then examined Tnfsf4 in human patients. They found that individuals with atherosclerosis contained a slightly different version of the gene than those without the condition. Wang, whose team publishes its findings online this week in Nature Genetics, says he is currently investigating how this difference leads to atherosclerosis.
"It's an excellent study," says Momtaz Wassef, a vascular biologist at the National Heart, Lung, and Blood Institute in Bethesda, Maryland. "Once this gene can be identified as a marker in people, we can treat the problem before its onset."