LONDON (Daily Mail) -- Researchers have identified a clutch of genes which raise the risk of heart disease.

Up to three-quarters of the population carry at least one of the six genes, raising the risk of having a heart attack by up to 40 percent. Carrying two copies of three of the genes raises a person's risk of heart disease by 78 percent -- the equivalent of being a heavy smoker. Understanding how such genes work could lead to new ways of treating and even preventing heart disease, which claims the lives of more than 100,000 Britons a year. Unraveling the genetics behind the condition could allow individuals to make lifestyle changes that could extend their lives. But there are also fears that insurance companies would cash in on the advances by hiking premiums for those at risk -- or even refusing to insure them altogether. Each of the six newly-identified genes increases the risk of heart disease by around 20 percent. As genes come in pairs, that means inheriting two flawed versions of a gene raises the risk by 40 percent. It is thought one in a thousand Britons carries two copies of three of the genes, raising their risk by 78 percent. For the few who carry six pairs of flawed genes, the risk is slightly higher, at 80 percent. Lead researcher Professor Nilesh Samani of the University of Leicester said: ""We are not talking about rare genetic variants here, but rather variants that are very common in our population. Many of these genetic variants are carried by between a quarter and three quarters of white Europeans. ""They are clearly very important and explain a significant proportion of heart attacks that occur."" The researchers, whose findings are published in the New England Journal of Medicine, said the results were an ""important step""' towards discovering the causes of heart disease. Professor Alistair Hall, from the University of Leeds, added: ""One person under 65 dies of a heart attack every 20 minutes. We believe all of these deaths are preventable."" The findings come just two months after Finnish scientists pinpointed another stretch of DNA responsible for doubling the risk of a heart attack