However, some people who have early-onset Alzheimer's don't have mutations in these three genes. That suggests that this early-onset form of Alzheimer's disease is linked to other genetic mutations that haven't been identified yet.
Early history Cigars, cigarettes Cancer by the carton Legal history Surgeon General's warning. (CNN) -- Tobacco was first used by the peoples of the pre-Columbian Americas. Native Americans apparently cultivated the plant and smoked it in pipes for medicinal and ceremonial purposes.
A Brief History of Tobacco Use. (Adapted from Tobacco.orgâs Tobacco Timeline by Gene Borrio.) The native people of the Americas considered tobacco a gift from the Great Spirit, and they used it in their religious practices. Today, experts believe that the tobacco we know began growing about 8,000 years ago.