8 July 2014
A genetic variant has been identified that increases the risk of cardiovascular disease, including stroke and heart attack.
The glycoprotein IIIa (PIA2) gene variant was identified from meta-analysis of data from around 50,000 people, by researchers at King's College London, and is present in around 10% of Caucasians.
The variant specifies the production of a glycoprotein found in platelets, specialised blood cells involved in blood clotting. In some (but not all) previous studies of the PIA2 variant, it has been associated with risk of stroke and myocardial infarction (MI).
The new research published in PLOS ONE, which was the largest analysis of the genetic fault to date, found the variant increased the risk of thrombotic stroke (i.e. caused by a blood clot) by more than 10% in carriers, and up to 70% in individuals with two copies of the variant. It was also found to increase the risk of heart attack in people under the age of 45; this effect in younger subjects is suggested to be in part due to the generally reduced levels of lifestyle cardiovascular risk factors such as smoking in this age group.
However, the researchers stress that the genetic variant plays a smal ler role than established risk factors such as high blood pressure and obesity in cardiovascular disease.
The increased risk conferred by the variant is likely to be caused by over-active platelets contributing to the blockage of arteries.
Author Professor Albert Ferro of King’s College London said: “In future it may be possible to reduce the chances of this happening by examining patients for this variant on a blood test, so that if they carry the PIA2 form - and especially if they carry two copies of it - such patients could be identified for a more determined reduction of risk factors such as smoking, high blood pressure or high cholesterol”.
However, it is not clear how clinically useful such a test would be in the general population.