The current report examines the association of single nucleotide polymorphisms (SNPs) with PTSD in the Comorbidity and Trauma Study (CATS), a case-control genetic association study of heroin dependence (Maloney et al., 2009; Shand et al., 2010; Nelson et al., 2012; Nelson et al., 2013,). The study’s cases [heroin dependent individuals ascertained from opioid replacement therapy (ORT) clinics] and controls (ascertained from economically-disadvantaged neighborhoods in proximity to the clinics) both report high prevalence of childhood and adult trauma exposure and lifetime PTSD. Association studies of PTSD have not commonly focused on drug dependent samples. Investigations (Driessen et al., 2008; Villagonzalo et al., 2011) in samples of alcohol and drug dependent individuals have observed very high rates of trauma exposure and PTSD including one report (Villagonzalo et al., 2011) that found 52.7% of methadone maintenance patients screened positive for PTSD. Conversely, in a recent study (Seal et al., 2012) of U.S. veterans of the Iraq and Afghanistan conflicts, those with PTSD were more likely to be prescribed opioids and to display behaviors suggestive of opioid misuse (i.e., prescriptions for multiple opioids; early refill requests).
