been effective in preventing relapse to heavy drinking and in reducing craving for alcohol (reviewed, e.g. by Sinclair, 2001; Bouza et al., 2004; Thorsell, 2013). Taken together, accumulating evidence implicates human µ-opioid receptor as an important determinant in the reinforcing effects of alcohol, making it a good candidate gene in the search of the genetic variation influencing the development of alcohol use disorders.
