The first gene linked directly to heart attacks has been isolated from an extended family in Iowa that has been plagued for generations by rampant coronary artery disease.
The gene, called MEF2A, plays a role in protecting the artery walls from building up plaque that can impede blood flow and lead to heart attacks, said Dr. Eric J. Topol of the Cleveland Clinic, head of a team that discovered the gene.
Topol said his team analyzed the genes of about 100 members of a family where heart disease and heart attack have been common for generations. They found that members with heart disease had a MEF2A gene that lacked some key bits of DNA. This apparently causes the arteries to thicken and become clogged.
"This is the first heart attack gene," Topol said. "Everyone who has this gene mutation is destined to have the disease. If you don't have this gene in this family, you appear to be free from developing this disease."
It would take additional studies to determine whether MEF2A plays a role in heart disease among people outside families where the mutation is inherited. The gene makes a protein that regulates some other genes, and Topol said those would be analyzed to see whether they could be linked generally to heart disease.
"We have learned from other genetic studies that once you get the first gene it starts to unlock the whole story," Topol said.
Details of the discovery were published in today's issue of the journal Science.