Adriani and Laviola 2004; Slotkin et al. 2008; Kota et al. 2009; Slotkin and Seidler 2009). Hence, the molecular mechanisms and neuroadaptive processes involved in adolescent exposure and adult exposure may differ considerably. The ramifications of these animal models for human genetic analysis are clear: If the etiology for the development of nicotine dependence differs by developmental stage, then the age at which smoking is initiated could be a critical moderator of SNP-associations for nicotine dependence.
