Alcohol dependence (AD) is a genetically complex disorder in which both genetic and environmental factors play crucial roles. Heritability has been estimated to be at least 50% for both men and women (Reich et al., 1998). Adaptation of GABAA receptors to ethanol exposure may play a role in the pathophysiology of AD (Harris et al., 1995, 1997, 1998; Iwata et al., 2000).
