Low synaptic 5-HT in humans and animals is associated increased drinking; medications that increase synaptic serotonin decrease alcohol intake; 5-HT-like drugs mimic alcohol intoxication; and higher platelet 5-HT reuptake is associated with developing AUDs (Ernouf et al., 1993; George et al., 1997; LeMarquand et al., 1994; Pandey et al., 1992; Rausch et al., 1991). A variant in the promoter region (5-HTTLPR) in the serotonin transporter gene (SLC6A4; chromosome 17q11.2) might relate to a lower LR (e.g., Cope et al., 2017; Hu et al., 2005) for a long (L) repeat length polymorphism associated with faster 5-HT reuptake (Hu et al., 2005). The LA variant might be associated with single dose oral alcohol challenge- and SRE-based low LR and higher rates of future AUDs (Hinkers et al., 2006; Hu et al., 2005; Schuckit et al, 1999).
