There is thought to be a strong hereditary element to Alzheimer's disease with the ApoE gene playing a significant part. Researchers from the Boston University School of Medicine studied 715 people taking part in the long-running Framingham Heart Study. 282 of them had one or both parents suffering from dementia, while the rest had parents who were unaffected. All the participants were tested for the presence of the ApoE gene and on verbal and visual memory tasks. Among people who were carriers of the ApoE gene those who had parents with Alzheimer's, or another dementia, scored significantly worse on the memory tasks - equivalent to approximately 15 years of brain ageing. The effect was largely limited to those participants who were carriers of disease risk between the generations.
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