New study of genes and heart disease

UK researchers have carried out a study of 500 pairs of twins that suggests genetic factors are more important in triggering coronary heart disease than non-genetic factors such as diet and lifestyle. The study, carried out by scientists at Guy's and St Thomas' Hospital, London, and Leeds University, was published in the Lancet.

The researchers examined the effects of various factors on the levels of blood-clotting proteins in identical and non-identical twins. High levels of these proteins are associated with an increased risk of coronary heart disease. The team found that although smoking, diet and lack of exercise play an 'extremely important' role in determining the levels of these proteins, the major risk factor was genetic make-up. 'As identical twins share exactly the same genes and non-identical twins half the same genes as each other, twin studies are extremely useful in separating these genetic and environmental components' said Dr Tim Spector, head of the twin research unit at Guy's and St Thomas' Hospital.

However, Dr Spector stressed that environmental factors were still important, adding that it was particularly important that people with a genetic susceptibility led a healthy lifestyle. Belinda Linden, of the British Heart Foundation, said: 'When we are fully able to identify those people with genetic abnormalities in clotting factors we may be able to help diagnose and treat those people most at risk'.