A team of international researchers believe they have identified a gene variation which could hold key information about the development of Alzheimer's disease.
Led by the Washington School of Medicine, scientists established that a particular gene has a clear link to increased levels of pTau protein, which are known to be an accelerant of Alzheimer's disease.
Results of the study, which involved 846 volunteers, were published in the Public Library of Science journal Genetics.
It is now hoped that this genetic marker could allow doctors to predict how quickly dementia will progress after diagnosis.
Dr Simon Ridley, head of research for the Alzheimer's Research Trust, commented: "This study provides fascinating new genetic insight into how Alzheimer's progresses.
"The findings could prove invaluable as we develop new treatments, helping to speed up our ability to assess the effectiveness of drugs and get them to patients."
More than one million people in the UK will be living with dementia by 2025, according to the Alzheimer's Society.
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