REVIEW ARTICLESGenetics of dopamine receptors and drug addiction: a comprehensive reviewFoll, Bernard Lea; Gallo, Alexandraa; Strat, Yann Lec; Lu, Linb; Gorwood, PhilipcAuthor Information aTranslational Addiction Research Laboratory, Centre for Addiction and Mental Health, University of Toronto, Toronto, Canada bNational Institute on Drug Dependence, Peking University, Beijing, China cINSERM U675 and University Paris VII, Paris, France Correspondence to Associate Professor Bernard Le Foll, MD, PhD, CCFP, Head, Translational Addiction Research Laboratory, Centre for Addiction and Mental Health, University of Toronto, 33 Russell Street, Toronto M5S 2S1, Canada E-mail: email@example.com Received 26 June 2008 Accepted as revised 11 October 2008 Behavioural Pharmacology: February 2009 - Volume 20 - Issue 1 - p 1-17 doi: 10.1097/FBP.0b013e3283242f05 Buy Metrics Abstract Drug dependence is a chronic, relapsing disorder in which compulsive drug-seeking and drug-taking behaviours persist despite serious negative consequences. Addictive substances, such as opioids, ethanol, psychostimulants and nicotine, induce pleasant states or relieve distress, effects that contribute to their recreational use. Dopamine is critically involved in drug addiction processes. However, the role of the various dopaminergic receptor subtypes has been difficult to delineate. Here, we will review the information collected implicating the receptors of the D1 family (DRD1 and DRD5) and of the D2 family (DRD2, DRD3 and DRD4) in drug addiction. We will summarize the distribution of these receptors in the brain, the preclinical experiments carried out with pharmacological and transgenic approaches and the genetic studies carried out linking genetic variants of these receptors to drug addiction phenotypes. A meta-analysis of the studies carried out evaluating DRD2 and alcohol dependence is also provided, which indicates a significant association. Overall, this review indicates that different aspects of the addiction phenotype are critically influenced by dopaminergic receptors and that variants of those genes seem to influence some addiction phenotypes in humans. © 2009 Lippincott Williams & Wilkins, Inc.