Minor linkage on chromosome 2 (LOD 1.5) is approximately 15–30cM from that reported for alcoholism (Hill et al., 2004), rank-transformed alcohol dependence symptom count in the IASPSAD sample (Kendler et al., 2006), heavy alcohol use in the Heart Study (Wyszynski et al., 2003), severity of alcohol use in Mission Indians (Ehlers et al., 2004), and maximum drinks in COGA (Saccone et al., 2005). Further, it is about 40–50cM from regions implicated in alcohol dependence (Reich, 1996), conduct disorder (Dick et al., 2004), and more recently, an alcohol dependence symptom score (Agrawal et al., 2008), in the COGA sample. In the current analyses, linkage was maximal in the older sample and sample truncation did not alter the result.
