The lifetime prevalence rate of alcohol dependence has been estimated at 12.5% to 13.2% (American Psychiatric Association, 1994; Hasin et al., 2007). Numerous family, twin, and adoption studies (e.g., Allgulander et al., 1991; Goodwin et al., 1973; Heath et al., 1997; Kendler et al., 1997; Reich et al., 1988) have suggested that alcohol dependence represents a heritable condition, and a growing number of studies have performed linkage analysis to identify genomic regions associated with the disorder (e.g., Bergen et al., 2003; Gelernter et al., 2008; Hill et al., 2004; Prescott et al., 2006). Nonetheless, few loci have shown replicable evidence of association with alcohol use phenotypes across studies (Dick and Bierut, 2006; Edenberg and Foroud, 2006). Thus, further studies are needed to identify genomic regions that confer risk for alcohol dependence.
