For example, researchers can inactivate, or knock out, a gene, creating a line of mice that lack a particular receptor or other protein thought to influence a specific genetic trait. Animals with an added gene are called transgenic. If these results are confirmed in humans, they may provide a means to help identify high-risk youth for targeted intervention programs. The use of microarrays is another powerful new technology in alcoholism research. This technique permits the simultaneous study of many genes and provides scientists with new power to understand changes in gene expression that relate to the vulnerability to developing alcoholism.
Genes direct the synthesis of proteins, such as receptors.
A gene's level of activity, therefore, can be used to obtain indirect information about its proteins. However, by using microarrays, alcohol scientists can track up to 10,000 selected genes simultaneously. As more alcoholism researchers begin to employ this procedure, it may become possible to identify virtually every gene and its protein that play a significant role in alcohol-related behavior. Such markers could enable researchers to confirm self-reported drinking behavior by study participants and could help clinicians monitor patients undergoing alcoholism treatment. Interest in using CDT as a biological marker of alcohol consumption has increased because of its relatively high sensitivity and specificity.