Since the first "alcoholism gene," dubbed DRD2, was found in 1990, researchers have hunted for DNA sequences that might predispose someone to a drinking problem. But DRD2's role in alcoholism has remained extremely controversial, and despite many efforts, no better candidates have emerged.
Many investigators are now taking a different tack. Instead of searching in families and populations of alcoholics for genes that might broadly confer a high risk for dependence, they are attempting to understand alcohol's effects and why they differ among people. In an explosion of studies, scientists have used rodents, fruit flies, zebra fish and roundworms to study characteristics such as sensitivity to intoxication and severity of withdrawal. By exploring alcohol's interaction with genes and the associated biological pathways, they hope to find clues to alcohol's addictive qualities.