The candidate genes that play a key role in nicotine addiction include those associated with the dopaminergic neurotransmitter system (e.g., DRD2, DRD3, DRD4), cellular transport system (e.g., SLC1A2, SLC6A4), serotonergic neurotransmitter system (e.g., HTR2A), nicotinic neurotransmitter system (e.g., CHRNA4, CHRNA5, CHRNA3, CHRNA7, CHRNB4), opioidergic activity (e.g., OPRM1), and nicotine metabolism (e.g., CYP2A6) ( Figure 1 nAChRs are primary targets of nicotine, nicotine exerts direct and indirect effects on other receptor systems (e.g., opioid, serotonergic, glutamatergic) that also mediate nicotine-induced behavioral and neural changes in humans
[56] The ravages of Old World diseases and Spanish exploitation reduced the Mexican population from an estimated 20 million to barely more than a million in the 16th century
The tobacco companies have steadily been building storage plants, largely on the South Side"
1 2 "White House Delays a Decision on Banning Menthol Cigarettes"
doi:10.1007/s00213-016-4391-x
commercial plans continue to gain traction despite a challenging macro-economic backdrop