Studies of populations at high risk for the future development of alcoholism.

This paper has reviewed information on possible markers of a biological vulnerability towards alcoholism. Most of the work is based on the premise that alcoholism is a genetically influenced disorder. The final development of alcoholism probably depends upon the interaction between biological and environmental influences. The emphasis placed on biology in this paper reflects both the discipline of the author and the probability that biological factors are easier to measure and, thus, more likely to be identified early in the course of a series of studies. At this point in the research, it is the methodologies being used that are of as much interest as the results themselves. In general, studies have taken advantage of persistent differences between alcoholics and controls to identify potential foci for studies of populations at high risk for the future development of alcoholism. Potential trait markers of greatest interest are those that not only differentiate alcoholics from controls, but that do not return to "normal" with extended abstinence. It is these measures that are generally used in comparisons of children of alcoholics with children of controls. Despite a diversity of methodologies, several potentially important leads towards identifying trait markers associated with a vulnerability towards alcoholism have been reported. Sons of alcoholics appear to show a decreased intensity of reaction to modest doses of ethanol and have lower amplitude of the P300 brainwave of the ERP. Other interesting and potentially important findings also require further evaluation. Once a behavior or test result is accepted as being significantly different in populations at high risk for alcoholism than in controls, much work remains before the actual presence of a trait marker for alcoholism can be established. Thus, this paper has described a series of research projects that are in their infancy, and much important work remains to be done.