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Molecular Genetics of Addiction

  1. Ming D Li

Published Online: 19 MAY 2010

DOI: 10.1002/9780470015902.a0022425



How to Cite

Li, M. D. 2010. Molecular Genetics of Addiction. eLS. .

Author Information

  1. University of Virginia, Virginia, USA

Publication History

  1. Published Online: 19 MAY 2010

This is not the most recent version of the article. View current version (14 AUG 2017)


Addictions to both licit and illicit drugs are common chronic brain disorders that are extremely costly to the individuals and society. Although genetics contributes significantly to vulnerability to these affective disorders, the susceptibility genes underlying them are largely unknown. Recent genome-wide linkage and association studies have implicated several common genomic regions and genes in the aetiology of addiction to multiple substances. For example, variants in the α2 subunit of gamma-aminobytric acid type A (GABAA) receptor have been found repeatedly in association with alcoholism and alcohol-related phenotypes. Recently, a cluster on chromosome 15q24/q25.1 that encompasses the genes for nicotine acetylcholine receptor subunits α5, α3 and β4 was implicated in addiction to tobacco and other substances as well. Current efforts aim not only to replicate these findings in independent samples, but also to determine the functional mechanisms of these associations.

Key Concepts:

  • Drug addiction is a chronic brain disorder.

  • Both human and animals studies reveal that addiction is determined not only by genetic and environmental factors, but also by their interactions.

  • Significant genetic overlaps exist among addictions to different substances.

  • It is important to determine not only genetic but also environmental factors involved in the aetiology of addictions.

  • Several genomic regions have been revealed to harbour susceptibility genes for multiple addictive disorders.

  • Genes such as those encoding GABAA and GABAB receptor subunits, neurexins 1 and 2, and some nicotinic receptor subunits are associated with addictions.

  • Determination of gene–environmental interactions is as important and challenging as determining gene–gene interactions.

  • Small microRNAs may play important roles in the mediation of expression of genes implicated in addictions.


  • genetics;
  • addiction;
  • dependence;
  • alcohol;
  • smoking;
  • opioid;
  • interaction