THOUSANDS of lives could be saved after the discovery of a genetic mutation which dramatically increases the risk of strokes.
The breakthrough could lead to screening tests to identify those at risk of large artery ischaemic strokes, which account for a third of all strokes.
Dr Peter Coleman, deputy director of research at The Stroke Association, said the discovery could also lead to “new ways of preventing stroke”.
Researchers from St George’s, University of London and Oxford University, have been leading a huge worldwide study on strokes. They found that 10 per cent of chromosomes carry a deviation on a gene called HDAC9.
Those who have two copies of the variant – one inherited from each parent – are at nearly twice the risk of this type of stroke.
Ischaemic strokes happen when a blood clot, air bubble or fat globules blocks an artery carrying blood to the brain.
Strokes cost the NHS £2.8billion a year, with 150,000 people suffering them, around 53,000 dying from them and another third are left partially paralysed and unable to speak.
The study’s co-leader, Professor Peter Donnelly, director of the Wellcome Trust Centre for Human Genetics, said: “If this discovery holds up more generally, it will move us closer to personalised medicine, where treatments and preventions can be tailored more precisely to individual patients.”
The mutant gene does not affect the likelihood of suffering the other main type of stroke, a haemorrhagic stroke, caused by bleeding deep inside the brain.