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 plant became the cornerstone of the Virginia economy. John Rolfe thought that Virginia might be an outstanding site for tobacco growth. Early attempts to sell Virginian tobacco had fallen short of expectations. Smokers felt that the tobacco of the Caribbean was much less harsh than Virginian tobacco.