Conventional wisdom has it that factors like diet, exercise and smoking put a person at greater risk of heart attack than genes. But an Icelandic company is in the process of developing a DNA test that will determine inherited vulnerability to heart attacks.
The company, deCODE Genetics, is encouraged by two separate studies that picked out a genetic profile that raises a person's vulnerability to heart attacks and coronary disease. The most dangerous of these variants is reported to increase the risk of heart attack at any age by up to 60 per cent. Men under 50 and women under 60 faced double the risk.
The journal Science published the two studies which looked for variants linked to heart attacks from among lakhs of single-letter DNA spelling mistakes referred to as single nucleotide polymorphisms or SNPs.
Interestingly, the two studies one conducted by deCODE and the other by Ruth McPherson, director of the University of Ottawa Heart Institute, Canada picked out an SNP close to two genes CDKN2A and CDKN2B. Trouble comes when you inherit two copies of this SNP variant in place of the two copies of this stretch of DNA everyone inherits, one from each parent.
How much risk does this SNP variant pose? The two studies say the risk is substantial: by as much as 60 per cent if you draw both SNP variants, says the deCODE study; by 30-40 per cent says the Ottawa study.
Buoyed by the findings, deCODE has said it plans to develop a test that include other genetic variants that lead to heart attacks. Once patients with a high genetic vulnerability are identified, they could be advised early on about lifestyle changes or be treated with cholesterol-reducing drugs.