CHRNA6 and Anxiety: To determine the role of the CHRNA6 3′-UTR SNP in nicotine-induced locomotion and anxiety-like behavior, we used an acute (1 × exposure) and a well-established sub-chronic (4-day) nicotine pretreatment paradigm to model nicotine initiation in adolescence [36,37] to evaluate nicotine-induced enhancement of locomotion and anxiety-like behaviors in humanized CHRNA6 3′-UTR SNP rodents.