Researchers investigating a known gene risk factor for Alzheimer’s disease discovered it is associated with lower levels of beta amyloid–a brain protein involved in Alzheimer’s–in cognitively healthy older people. The findings suggest that a mechanism other than one related to beta amyloid accumulation may influence disease risk associated with the gene. The study, by researchers at the National Institute on Aging (NIA) at the National Institutes of Health, was published online September 27, 2012 in the journal Biological Psychiatry.