Variations in a gene called APOE are known to affect people's chances of developing Alzheimer's disease. Researchers from the University of Pennsylvania School of Medicine, Massachusetts General Hospital and Harvard Medical School studied 91 people with Alzheimer's disease. They found that people with one variation of the gene - the one linked to an increased risk of Alzheimer's disease - performed worse on memory tests and had more abnormalities in the part of the brain that deal with memory. People with the other variation did worse in tests of attention, language and executive function and had more prominent abnormalities in the relevant areas of their brains.
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