Trauma exacerbates the effect of genetic variants in the dopamine system on cannabis use

s / Drug and Alcohol Dependence 156 (2015) e102–e182 e151 Preliminary analyses show significant group by visit interactions for breath CO (p=0.006) and urinary cotinine (p=0.03), with lower CO and cotinine levels in the Incentive vs. Control group. Final biochemical and abstinence data will be available for presentation at the June 2015 meeting, as will additional measures of nicotine withdrawal, craving, and respiratory symptomatology. Conclusions: These results suggest that an incentive-based intervention may be feasible and effective in producing initial smoking abstinence in this hard-to-treat sample of smokers.Financial support: T32 DA007242, P20 GM103644. http://dx.doi.org/10.1016/j.drugalcdep.2015.07.410 Trauma exacerbates the effect of genetic variants in the dopamine system on cannabis use Jacquelyn L. Meyers1, Monica Uddin2, Sandro Galea1, Allison Aiello3, Derek Wildman2, Karestan C. Koenen1 1 Epidemiology, Columbia University, New York, NY, United States 2 University of Champagne-Urbana, Urbana, IL, United States 3 University of North Carolina Chapel Hill, Chapel Hill, NC, United States Aims: Although cannabis use is heritable, few studies have examined genetic risk for cannabis use alone, and of the studies that have been published, few genetic risk variants have been identified. In addition, the evidence for gene–environment interactions (GxE) in substance use behaviors is growing, with several GxE studies indicating that the effects of specific genetic variants are exacerbated by traumatic experiences. However, there have been no published GxE studies for cannabis involvement to date. Several biological systems that potentially incur risk for cannabis involvement have been identified via neurobiological studies, including variation in the dopaminergic system. For example, Volkow and colleagues investigated the effects of chronic cannabis use on the human brain using PET imaging, and found that cannabis abusers showed markedly blunted responses when challenged with methylphenidate, a drug that elevates dopamine. Methods: In this study, we provide evidence of association between sets of genetic variants in the dopamine system (96 single nucleotide polymorphisms across DRD1–DRD4) and frequency of cannabis use (days/month, within the past 30 days) in two independent majority African-American population based samples (Detroit Neighborhood Health Study, n=788; Grady Trauma Project, n=3752; p 33% treating prescription stimulants and prescription depressants, and ∼50% treating alcohol and marijuana. Over 50% referred youth to specialty care if use includedheroinormethamphetamine. The use of standardized assessments was rare and only ∼33% reported use of motivational interventions. Cognitive behavioral therapy was the predominate treatment delivered in individual youth sessions (85%); 75% provided family sessions but 90% of cases, it is critical that PPs be included in our effort to improve adolescent treatment quality.Financial support: P50-DA027841. http://dx.doi.org/10.1016/j.drugalcdep.2015.07.412 Trends in use of and attitudes toward marijuana among youth before and after decriminalization: The case of California 2007–2013 Richard Miech, Lloyd A. Johnston, Patrick O’Malley, Jerald Bachman, John Schulenberg, Megan Patrick University of Michigan, Ann Arbor, MI, United States Aims: This analysis examines decriminalization as a risk factor for future increases in youthmarijuana acceptance and use. Specifically, we examine marijuana-related behaviors and attitudes of 8th, 10th, and 12th graders in California as compared to other U.S. states during the years before and after California passed legislation in 2010 to decriminalize marijuana. Methods: Data come from the annual Monitoring the Future study, which since 1975 has used questionnaires administered in classrooms to survey nationally representative samples of