The breakthrough could lead to new treatments – and even ways of preventing the killer disease in the first place.
With at least 820,000 Britons diagnosed with a form of dementia, ways to beat it are desperately being sought.
The latest study centres on a protein that appears to stop the build-up of toxic plaques that ravage the brain of Alzheimer’s sufferers.
The American research was led by Professor Joel Buxbaum.
He said: “This result was completely unexpected when we started.
“But now we realise that it could indicate a new approach for Alzheimer’s prevention and therapy.”
The protein is commonly found in the liver, where its presence tends to be more hazardous than beneficial.
