A team of scientists have confirmed six new genetic variants that increase the likelihood of developing coronary artery disease. "We are not talking about rare genetic variants here, but rather variants that are very common in our population," says Nilesh Samani, M.D., British Heart Foundation chair of cardiology at the University of Leicester, and lead author on the paper.
"Many of these genetic variants are carried by a quarter to three-quarters of white Europeans. They are clearly very important and explain a significant proportion of the heart attacks that occur."
Carrying one copy of the newly-identified variants increases the chances of developing heart disease by at least 20%. Having two such copies would increase the risk by over 40%.
The first important clues to the identities of these variants came from a genome-wide analysis conducted in almost 2,000 people with coronary artery disease and 3,000 healthy controls as part of the Wellcome Trust Case Control Consortium. The study used the genome-wide Affymetrix GeneChip 500K Arrays. The findings were then compared with the German MI Family Study, with almost 900 cases and 1,600 controls.
The investigators found that changes in our DNA on chromosomes 2, 6, 10, and 15 and two on chromosome 1 were associated with increased risk of developing coronary artery disease and heart attacks. The study also confirmed the importance of a variant on chromosome 9, previously identified in independent research.
Although the researchers know that some of the variants implicated are involved in cell growth and cell division, they are now working to understand exactly how this leads to heart disease.
The research was conducted by scientists from the University of Leicester, the University of Leeds, the University of Lubeck, and the University of Regensburg. The study was published in the July 18 online edition of the New England Journal of Medicine.