Researchers in Iceland believe they have found a mutation that could protect people against Alzheimer's disease.
According to the study, a mutation known as A673T in the APP gene disrupts the production of amyloid-beta, a hallmark of the disease, the Alzheimer's Society reported.
The findings have caused shock among academics, as the APP gene is usually associated with the development of Alzheimer's.
APP is well known to be a pre-cursor to Alzheimer's disease and has not previously been linked to its prevention.
Researchers made the discovery when analysing the cognitive function of a group of people living in care homes.
Participants were comprised of people with and without the gene mutation and it was found that those with it had less cognitive decline.
A spokesperson from the Alzheimer's Society commented: "We still have a lot to learn about what happens in the brain but this research offers new insight into a gene we already know is linked to the disease."
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