Co-Occurring Risk Factors for Alcohol Dependence and Habitual Smoking Results From the Collaborative Study on the Genetics of Alcoholism

Smoking and alcohol dependence frequently occur together, and both behaviors are determined in part by genetic influences. The Collaborative Study on the Genetics of Alcoholism (COGA), which is investigating the genetic factors contributing to alcohol dependence, also allows for analyses of the genetic factors determining smoking. Using a sample comprised of alcoholics and their closest (i.e., first-degree) relatives as well as a community-based control sample, COGA investigators found that both alcohol dependence and habitual smoking were transmitted within families. This familial transmission resulted from both common and drug-specific influences, which likely include genetic factors. Further genetic studies (i.e., candidate gene studies and genomic screening approaches) have identified several DNA regions that may contain genes that confer a susceptibility for alcoholism. Some of those genes also may contribute to the risk for habitual smoking. KEY WORDS: AOD (alcohol or other drug) dependence potential; smoking; gene expression; dopaminergic receptors; genetic linkage; AODR (AOD related) genetic markers; genetic screening method; chromosome; DNA replication; genetic variance; risk factors Vol. 24, No. 4, 2000 233 In the United States, excessive alcoholuse is a serious public health problem.At some time in their lives, 19 percent of men and 8 percent of women have been diagnosed with alcohol dependence as defined in the American Psychiatri