What Causes Alcoholism? Researchers are attacking this question from many angles, producing several different lines of evidence: Changes in the functioning of neurotransmitter systems. With continued use, alcohol loses some of its effect on GABA and glutamate, which may be one of the pathways to tolerance. This process is not clearly understood, but some researchers believe neurons may compensate for alcohol's inhibitory effects by altering the number or activity of receptors sensitive to GABA and glutamate (Nietzel, Speltz, McCauley, & Bernstein, 1998). Genetic predisposition. The risk of alcohol abuse is seven times greater among the first-degree relatives of alcoholics than among first-degree relatives of nonproblem drinkers (Merikangas, 1990). This predisposition to alcoholism may in part be traced to a gene, located on chromosome 11, that controls one type of dopamine receptor and enhances the rewarding effects of alcohol. Other possible genetic causes under investigation include fewer than normal dopamine receptors (Research Institute on Addictions, 1997; Washington Post, March 9, 1998); slower metabolism of alcohol in the brain (thus increasing feelings of reward and pleasure); faster metabolism of alcohol in the liver (allowing a person to consume more alcohol); and lower levels of serotonin (Nietzel and others, 1998). Learned behavior. The history of alcoholism in some families may reflect learned behavior. Long before we take our first drink, we have learned about the physical and psychological effects of alcohol by observing parents or other adults (Zucker & Fitzgerald, 1991; Noll, Zucker, & Greenberg, 1990). Age of onset as a contributing factor. Those who start drinking during their teens increase their chances of becoming addicted to alcohol. More than 40 percent of people who begin drinking before the age of 15 will be classified with alcohol dependence at some time in their lives. This compares to 24 percent for those who begin drinking at age 17 and approximately 10 percent for those who begin drinking at the ages of 21 and 22 (NIAAA, 1998). Let's take a closer look at alcohol use among young people today and examine some its dangers. Alcohol Use Among Young People