Project description:<p>This collaboration of Australian and American investigators aims to identify genes associated with liability for heroin dependence. The project uses a case-control design in which cases met lifetime DSM-IV criteria for heroin dependence. Controls included assessed individuals who did not meet DSM-IV heroin dependence criteria and unassessed general population controls. Cases and controls were obtained from the several large investigations including: The Comorbidity and Trauma Study, Heroin Dependence in Western Australia, the OZ-ALC Study, a Twin Study of Mole Development in Adolescence, and ongoing genetic studies of substance dependence conducted by investigators at Yale and collaborating institutions. These projects are briefly described below.</p> <p>The Comorbidity and Trauma Study (PI: Elliot Nelson), a retrospective case-control study examining genetic and environmental factors contributing to heroin dependence liability. The study was funded by the National Institute on Drug Abuse (NIDA), and was run in collaboration with Washington University, the Queensland Institute of Medical Research (QIMR), and the National Drug and Alcohol Research Centre (NDARC), University of New South Wales. Case participants were recruited from maintenance clinics in the greater Sydney area. Control participants were recruited from employment centres and community centres, open street malls, and local press servicing the same geographical area as the opioid maintenance treatment clinics and either denied recreational use of opioids or had used these drugs recreationally fewer than 11 times lifetime. The prevalence in these individuals of non-opioid licit drug dependence and illicit drug dependence as well as childhood trauma exposure and other psychiatric disorders is elevated considerably versus estimates of similar measures in Australian general population samples. Participants provided blood samples as a source of DNA and completed a comprehensive psychiatric diagnostic interview based on the Semi-Structured Assessment of the Genetics of Alcoholism - Australia (SSAGA-OZ) augmented with sections drawn from other instruments assessing childhood trauma exposure, family history, and screening for borderline personality disorder.</p> <p>Heroin Dependence in Western Australia (PI: Sybille Schwab) is a study focusing both on genetic contributions to heroin dependence and response to naltrexone treatment of the disorder. Participants completed a clinical assessment and provided blood samples during their treatment at the Perth Naltrexone Clinic now name as the Fresh Start Recovery Programme. Funding for the project was provided by the Australia Government's National Health and Medical Research Council (Grant # 513862; PI: Sybille Schwab)</p> <p>Affected subjects from ongoing genetic studies of substance dependence conducted by investigators at Yale (PI: Joel Gelernter) and collaborating institutions were collected in the course of several NIDA-funded studies. Those included in the current set were assessed by means of the SSADDA (Semi-Structured Assessment for Drug Dependence and Alcoholism). All are opioid dependent European-Americans, and all list heroin as the opioid must used. Most were collected at Yale University School of Medicine or University of CT School of Medicine under the supervision of Drs Joel Gelernter and Henry Kranzler. Control subjects were also collected in the course of several NIDA- and NIAAA-funded studies. Those included in the current set were assessed by means of the SSADDA (Semi-structured Assessment for Drug Dependence and Alcoholism). Most were collected at Yale University School of Medicine or University of Connecticut School of Medicine under the supervision of Drs Joel Gelernter and Henry Kranzler.</p> <p>The OZ-ALC Study (PI: Andrew Heath) consists of a large group of twins and their family members ascertained from the general population Australian Twin Registry who have participated in ongoing research projects. For the control investigation, we have selected individuals who do meet criteria for illicit drug dependence who have had GWAS genotyping with the Illumina Human CNV370-Quad. Inclusion of individuals with alcohol dependence or nicotine dependence was minimized. For a more detailed description of the study, please see this <a href="./study.cgi?study_id=phs000181">link</a>.</p> <p>The Twin Study of Mole Development in Adolescence (PI: Nick Martin) is an ongoing investigation of melanocytic naevi funded by the Australian Government's National Health and Medical Research Council (Grant # 389891; PI: Nick Martin). For the current project, unassessed parents of these twins will serve as a control group. These individuals will either have been previously genotyped with the Illumina Human 610-Quad BeadChip or will be genotyped as part of the current project. Parents have largely survived the period of risk for heroin dependence, and by virtue of their participation in this research, are very likely to have a prevalence of heroin dependence lower than that in the general population (i.e., <0.7%).</p>
Project description:Noncoding RNAs, especially microRNAs (miRNAs) have been implicated in the regulation of neuronal functions, such as learning, cognition and memory formation. However, the particular miRNAs involved in drug-induced behavioral plasticity are largely unknown. Here we report a novel regulator, miR-218, that inhibits heroin-induced behavioral plasticity. Network propagation-based method revealed several miRNAs that play key roles in drug-addiction, among which, miR-218 was decreased in nucleus accumbens (NAc) after chronic exposure to heroin. Lentiviral overexpression of miR-218 in NAc could inhibit heroin-induced reinforcement in both conditioning place preference (CPP) test and heroin self-administration (SA) experiment. Luciferase activity assay indicated miR-218 could regulate neuroplasticity related genes and directly target Mecp2 3’UTR. Consistently, Mecp2-/y mice exhibited reduced heroin seeking behavior in CPP test. These data reveal a functional role of miR-218 and its target, Mecp2, in the regulation of heroin-induced behavioral plasticity.
Project description:<p>Our principal goal was to determine the chromosomal locations of genetic variations associated with increased vulnerability to heroin dependence. This goal was attained by identifying specific DNA markers that are genetically linked to heroin dependence. We collected blood and diagnostic information (using a structured diagnostic interview) from 1230 people (sib-pairs) having DSM-IV defined heroin dependence as well as from their parents and other affected and unaffected siblings, when possible. Genotype and clinical data was archived using database software. We conducted a multipoint linkage analysis using the guidelines of Lander and Kruglyak to assert statistical significance, and followed up on regions of interest with a dense set of markers to evaluate candidate genes</p>
Project description:To determine the differential miRNA levels in heroin addicts, we comparatively profiled plasma miRNA expression of heroin abusers and healthy controls using Agilent Human miRNA Array.
Project description:Several studies have investigated changes induced by drug exposure, but few reports have described changes that persist following relapse. In the present study, genome-wide analysis of gene expression was conducted in rats that expressed behavioral incubation of heroin-seeking and goal-directed behavior. The medial prefrontal cortex (mPFC) is important in mediating goal-directed behavior and also was the target of this analysis. Rats were trained to self-administer heroin (0.06 mg/0.2 ml infusion) during 3 hour daily sessions for 14 days. Following the self-administration period, rats were reintroduced to the self-administration chambers for a 90-minute extinction session. The extinction session occurred either 1 day or 14 days following the final self-administration session. Behavioral data demonstrated incubation (increased expression) of heroin-seeking and goal-directed behavior after the 14 day abstinent period. Whole genome analysis was performed and selected results were confirmed by quantitative real-time PCR (RT-qPCR). Microarrays identified 66 genes whose expression was identified as changed by at least 1.4 fold (p<0.02) following 14 days of abstinence and the 90-minute extinction session, and seven of the genes on which RT-qPCR was performed were confirmed (BDNF, Calb1, Dusp5, Dusp6, EGR1, NPY, RGS2). Ontological analysis indicates that several of the genes with changed expression in this study are important for behavior and learning. The importance of drug-seeking behavior and memory of previous sessions of drug-taking suggest that such genes may be important for relapse. The global gene expression analysis adds to the knowledge of heroin-induced changes and further highlights similarities between heroin and other drugs of abuse. Keywords: heroin self-administration cRNA from 6 rats that self-administered heroin was compared to cRNA from 5 rats that received yoked infusions of saline.