Scientists have identified two new genes that are linked to a person's risk of coronary heart disease (CHD).
The findings, based on a study of the DNA of more than 190,000 people, could lead to the discovery of new therapies to prevent heart attacks, the British Heart Foundation (BHF) believes.
Researchers found that changes in the DNA code which alters a gene called ANGPTL4 are linked to a reduced risk of CHD. They also found that errors in a more mysterious gene called SVEP1 were linked to an increased risk of CHD.
The BHF points out that CHD is responsible for nearly 70,000 deaths every year, making it the UK's single biggest killer, and most CHD deaths are caused by a heart attack.
The findings, published in the New England Journal of Medicine, are "potentially very important", according to lead researcher BHF Professor Sir Nilesh Samani, of Leicester University.
He said: "Until now many of the DNA alterations we have identified that affect CHD are in regulatory regions of our DNA which are less easy to target in terms of developing new treatments. Here, by implicating specific genes and the proteins they produce, we are a step nearer developing much-required new treatments."
ANGPTL4 helps to block an enzyme which is involved in removing a type of fat from the bloodstream.
The researchers also discovered a non-functioning form of the ANGPTL4 gene. People with this type of ANGPTL4 had a 53% lower risk of CHD and lower levels of the fat, called triglycerides, in the bloodstream.
More study into the impact of the SVEP1 gene on CHD risk needs to be carried out.
The researchers noted a small association with SVEP1 alterations and higher blood pressure, which is a major risk factor for CHD, but they would like a deeper understanding of how the gene works.
Shannon Amoils, of the BHF, believes the value of this large genetic study is in providing "strong additional evidence to suggest there is a link between how the body processes triglycerides and coronary heart disease".
An international team of scientists carried out the study, which was part-funded by the BHF and the National Institute for Health Research (NIHR).