A team of international scientists have identified nearly two dozen new genetic risk factors for stroke, marking a significant advance in what is known about the underlying causes of one of Australia's biggest killers.
Stroke kills more women than breast cancer and more men than prostate cancer.
High blood pressure, high cholesterol and smoking are all known to increase a person's risk of stroke but the underlying molecular causes have remained poorly understood.
To unravel the complexities of the disease, researchers analysed the DNA samples of 520,000 people from Europe, North and South America, Asia, Africa and Australia.
They identified 22 new genetic variants associated with stroke, tripling the number already linked to stroke risk.
Some of these genetic risk factors contributed to specific biological mechanisms involved in stroke, while others contributed to stroke susceptibility.
It's hoped the findings of the study, the largest of its kind in the world, will lead to new drug treatments and the possibility of personalised, evidence-based treatments for the complex disease.
"This work provides evidence for several novel biological pathways involved in stroke that may lead to the discovery of novel drug targets," said study co-author and neurologist, Associated Professor John Cole at the University of Maryland School of Medicine.
Australian stroke expert Professor Chris Levi from the Australian Stroke Genetics Collaboration and Hunter Medical Research Institute says unravelling the genetics of stroke is particularly important for understanding why stroke affects the young.
"About a third of strokes occur in people under 55," said Prof Levi.
"For many young stroke patients they don't have the identifiable risk factors. They don't have high blood pressure, they don't have high cholesterol, they don't have atrial fibrillation, they don't smoke; so why do they have a stroke?" he said.
"This work could well unravel a lot of those unanswered questions."
The Stroke Foundation reminds Australians, however, that simple lifestyle interventions are still the best way to prevent stroke.
"Stroke is largely preventable by adopting a healthy lifestyle, which includes managing cholesterol, eating healthily, being active, avoiding smoking and not drinking too much alcohol," said Stroke Foundation Clinical Council Chair Associate Professor Bruce Campbell.