conduct disorder (Dick et al., 2004), which are highly co-morbid with alcohol dependence (Hasin et al., 2007). A third locus was identified at chromosome 18p11.21–p11.2, and notably, multiple studies from four independent samples have linked this region to alcohol dependence-related phenotypes (Hill et al., 2004; Kuo et al., 2006; Prescott et al., 2006; Schuckit et al., 2001; Schuckit et al., 2005; Wilhelmsen et al., 2005).
