Article

Gene X Abstinence Effects on Drug Cue Reactivity in Addiction: Multimodal Evidence

Departments of Psychiatry and Neuroscience, Icahn School of Medicine at Mount Sinai, New York, New York 10029, Medical Department, Brookhaven National Laboratory, Upton, New York 11973, Department of Psychology, Stony Brook University, Stony Brook, New York 11794, National Institute on Drug Abuse, Bethesda, Maryland 20892, and National Institute on Alcohol Abuse and Alcoholism, Bethesda, Maryland 20892.
The Journal of Neuroscience : The Official Journal of the Society for Neuroscience (Impact Factor: 6.75). 06/2013; 33(24):10027-36. DOI: 10.1523/JNEUROSCI.0695-13.2013
Source: PubMed

ABSTRACT Functional polymorphisms in the dopamine transporter gene (DAT1 or SLC6A3) modulate responsiveness to salient stimuli, such that carriers of one 9R-allele of DAT1 (compared with homozygote carriers of the 10R-allele) show heightened reactivity to drug-related reinforcement in addiction. Here, using multimodal neuroimaging and behavioral dependent variables in 73 human cocaine-addicted individuals and 47 healthy controls, we hypothesized and found that cocaine-addicted carriers of a 9R-allele exhibited higher responses to drug cues, but only among individuals who had used cocaine within 72 h of the study as verified by positive cocaine urine screens (a state characterized by intense craving). Importantly, this responsiveness to drug cues was reliably preserved across multimodal imaging and behavioral probes: psychophysiological event-related potentials, self-report, simulated cocaine choice, and fMRI. Because drug cues contribute to relapse, our results identify the DAT1R 9R-allele as a vulnerability allele for relapse especially during early abstinence (e.g., detoxification).

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Available from: Muhammad Parvaz, Oct 24, 2014
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