Project description:Genetic factors are strongly implicated in the susceptibility to develop externalizing syndromes such as attention deficit/hyperactivity disorder (ADHD), oppositional defiant disorder, conduct disorder, and substance use disorder (SUD). Variants in the ADGRL3 (LPHN3) gene predispose to ADHD and predict ADHD severity, disruptive behaviors comorbidity, long-term outcome, and response to treatment. In this study, we investigated whether variants within ADGRL3 are associated with SUD, a disorder that is frequently co-morbid with ADHD. Using family-based, case-control, and longitudinal samples from disparate regions of the world, recruited either for clinical, genetic epidemiological or pharmacogenomic studies of ADHD, we assembled recursive-partitioning frameworks (classification tree analyses) with clinical, demographic, and ADGRL3 genetic information to predict SUD susceptibility. Our results indicate that SUD can be efficiently and robustly predicted in ADHD participants. The genetic models used remained highly efficient in predicting SUD in a large sample of individuals with severe SUD from a psychiatric institution that were not ascertained on the basis of ADHD diagnosis, thus identifying ADGRL3 as a risk gene for SUD. Recursive partitioning analyses revealed that rs4860437 was the predominant predictive variant. This new methodological approach offers novel insights into higher order predictive interactions and offers a unique opportunity for translational application in the clinical assessment of patients at high risk for SUD
Project description:Ex vivo large-scale proteomic analysis using LC-MS/MS in postmortem brains of patients with substance use disorder and controls. Brain tissue was collected postmortem after consent from the next of kin. As part of the clinical information, medical records were obtained and a detailed psychological autopsy was performed on all participants by interviewing the next-of-kin. Information regarding the psychiatric clinical phenotypes (evidence of depression, mania, and psychosis) stressful life events, age of drug use onset, types of drugs used, smoking and drinking history, and any co-morbidities, was obtained. A diagnosis of substance use disorder was confirmed based on the psychological autopsy, detailed medical records, and review of all relevant case information by three psychiatrists at a consensus meeting. The cause of death was obtained from the medical examiner’s report and toxicological findings after death.
Project description:Alcohol use disorder (AUD) has a profound public health impact and understanding of the molecular mechanisms underlying the development and progression of AUD remain limited. Many genetic risk loci have been identified for AUD or alcohol consumption, though the neurobiological mechanisms underlying these loci remain largely unknown. DNA methylation (DNAm) differences between individuals with and without AUD can provide insight into the mechanisms that predispose to AUD and consequences of AUD itself. Here, we provide Illumina HumanMethylation EPIC array data generated in nucleus accumbens and dorsolateral prefrontal cortex, both addiction relevant brain tissues, from 119 decedents of European ancestry: 61 controls and 58 cases. From these data we have conducted an epigenome-wide association study (EWAS) and identified several CpG associations with AUD. A subset of the identified CpGs map to genes that were previoulsy identified as associated with substance use behaviors in genetic studies, but the other CpGs map to genes previoulsy unassociated with substance use behaviors and are novel.
Project description:The investigators propose to develop, implement, and evaluate a novel Colorectal (CRC) screening patient navigator program for patients with Mental Health (MH) and /or Substance Use Disorder (SUD) receiving care at Massachusetts General Hospital Charlestown. The study will involve randomly assigning eligible patients to early intervention or usual care/delayed intervention groups. The investigators believe this random assignment is ethical because Patient Navigation (PN) is an extremely limited resource, and all patients identified as eligible could not be contacted by the navigators in a short period of time. Thus the investigators will randomly assign access to PN during the study period, and then allow all patients to be navigated and screened after the study period is over. As a result, all eligible patients will be referred for PN, but the timing of the referral will be randomly assigned.