Rutgers-Newark researchers have shown that a genetic variant specific to African ancestry alters the brain in a way that could foretell the eventual development of Alzheimer's Disease. At the same time, their study revealed some good news: A far more well-known genetic mutation doesn't seem as malevolent in African Americans as it is in people of primarily European descent. The finding may help explain why African Americans develop Alzheimer's at more than twice the rate than people whose genetic ancestry is mostly European. The results will appear in the May edition of Neurobiology of Aging.