Genetics of alcoholism and substance abuse.

Twin studies have demonstrated that addictive disorders are genetically and environmentally influenced. Our knowledge of behavioral differences predisposing to addiction is advancing rapidly, particularly in alcoholism but also in the other addictions, through studies on animals and humans. Recently, linkage analyses in humans and rodents have pointed to genomic regions harboring genes which influence addiction or drug-associated behaviors. There is increasing evidence that the addictions have common as well as distinct neurobiological pathways. These advances in the understanding of the genetics of addictive disorders should facilitate the development of specific pharmacotherapies and the more accurate targeting of therapies using molecular diagnostic approaches.