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.
However, the tide started to turn on the debate over whether tobacco was harmful in 1950, when Dr. Ernst L. Wynder published a groundbreaking report in the Journal of the American Medical Association that demonstrated that smoking caused cancerous tumors in mice. And the rest, as they say, is history.