'Dementia gene' may guard against decline associated with parasitic disease
"While being an E4 carrier is the strongest risk factor to date of Alzheimer's dementia and cognitive decline in industrial populations, it is associated with greater cognitive performance in individuals facing a high parasite and pathogen load, suggesting advantages to the E4 allele under certain environmental conditions," said Benjamin C. Trumble, Ph.D., a researcher involved in the work at the School of Human Evolution and Social Change and the Center for Evolution and Medicine at Arizona State University in Tempe, Arizona. "The current mismatch between sedentary postindustrial lifestyles and active parasite-rich lifeways experienced throughout most of human history may be critical for understanding genetic risk for cognitive aging." Trumble and colleagues examined cognitive performance and parasite exposure data from a remote population of forager-horticulturalists in the Bolivian Amazon , called the Tsimane. The Tsimane experience high parasite loads,...