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.
This paper will trace the history of tobacco from its use by Native Americans through the end of the 19th century when mechanization and mass marketing started to make tobacco production the major industry it has become. Tobacco is a name used for plants of the genus Nicotiana of the Solanaceae (nightshade) family.