A new gene has been discovered, which could increase the risk of older people with it developing Alzheimer's.
Researchers at the University of Miami Miller School of Medicine have identified the MTHFD1L gene.
They note subtle differences in those possessing it, with some developing Alzheimer's and some not.
Commenting on the findings, published in the journal PLoS Genetics, lead researcher Margaret Pericak-Vance explained: "Identifying this gene is important because the gene is known to be involved in influencing the body's levels of homocysteine, and high levels of homocysteine are a strong risk factor for late-onset Alzheimer disease."
Co-author Dr Joseph Buxbaum added that a better understanding of the gene may provide insight into the way blood vessel function affects Alzheimer's.
Research published earlier this week by scientists at the University of California suggested that the development of dementia could be linked to the type of profession patients worked in.
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