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.
The Old World encountered tobacco at the dawn of the European Age of Exploration. On the morning of October 12, 1492, Christopher Columbus set foot on a small island in the Bahamas.