Neurobiological and genetic aspects of the etiology of alcoholism.

In contrast to humans, most animals will not voluntarily consume alcohol to the point of intoxication nor to the point of development of tolerance and physical dependence. Since there is good evidence for a genetic component to human alcoholism, we explore the possibility that the presence of alcohol in the environment during human evolution has contributed to this difference in behavior from that observed in lower animals. We then review the biologic basis for genetic influences on various aspects of alcohol-related behaviors in both humans and lower animals. Thus, the evidence for genetic influences on rate of alcohol metabolism, preference, central nervous system depressant effects. tolerance, and dependence are briefly reviewed. The technique of selective breeding for alcohol-related behavior is described and compared to the process of natural selection that may be occurring in the human population.