Hardly surprisingly getting old is the main risk factor for Alzheimer's disease but the next most significant one is having a family history of the condition. Lisa Mosconi from New York University led a team of researchers using PET (positron emission tomography) scans to study the brains of healthy adults to see whether they were developing the plaques of beta amyloid protein that are characteristic of Alzheimer's. The team scanned 42 participants. 14 of them had mothers with Alzheimer's, 14 of them had fathers with Alzheimer's and 14 had unaffected parents. Those participants with a family history of the illness were more likely to have the plaques and those whose mothers had the illness were particularly at risk, being four times more likely to have them.
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