Three G protein-coupled NPY receptor genes, NPY1R, NPY2R, and NPY5R have been shown to be associated in animals with alcohol preference (Eva et al., 2006; Thiele and Badia-Elder, 2003; Thorsell and Heilig, 2002) and withdrawal (Bison and Crews, 2003; Thiele et al., 2004b; Thorsell et al., 2007; Valdez and Koob, 2004; Woldbye et al., 2002). These three genes are located on chromosome 4q31-q32 (Lutz et al., 1997; Wraith et al., 2000), near the edge of a broad linkage peak for the risk for alcohol dependence identified in the Collaborative Study on the Genetics of Alcoholism (COGA) sample (Reich et al., 1998; Reich, 1996; Williams et al., 1999).
