In the past alcohol and drug addictions were seen as character failings, yet today they are viewed as treatable diseases of the brain. So what could be better than finding a gene linked directly to alcoholism? One team of researchers might say identifying a whole network of genes for alcoholism. In a new study, researchers at The University of Texas at Austin discovered certain sets of genes working together as a network in alcoholics, though not in nonalcoholics. Their findings could lead to future treatments and therapies for alcoholics and possibly help doctors screen for alcoholism.

"We now have a much clearer picture of where specific traits related to alcohol dependence overlap with specific expressions in genetic code," said Dr. R. Adron Harris, director of the UT’s Waggoner Center for Alcohol and Addiction Research and co-author of the study.

Genetic or Lifestyle Disease?

Alcoholism is a chronic and often progressive disease. Those who suffer from alcoholism cannot consistently predict how much or how long they will drink. They have problems controlling alcohol, being preoccupied with drinking, and continuing to drink even when it causes problems. They also may experience withdrawal symptoms when rapidly decreasing or stopping their use of alcohol. Plus, alcoholics find themselves needing to drink more over time as their physical dependence increases.

While scientists have known for some time that genetics play a role in alcoholism and other addictions, they also understand the tendency to be dependent on alcohol is more complicated than the simple presence or absence of any one gene. Considering that alcoholism seems to run in families and so appears to be a gene-based disease, there are questions concerning the fact that binge drinking — consuming five or more drinks in a row for a man, or four drinks for a woman — leads to the faster development of alcoholism. If binge drinking can influence dependency, it would suggest the disease is also behavior-based and not only a matter of genes. How exactly do genetics interact with behavior in alcoholism?  

To learn more about the genetics underlying alcoholism, the team of UT Austin scientists put to use bioinformatics technology of RNA sequencing — essentially the latest tools in both computing and genetics. After obtaining brain tissue from alcoholics and nonalcoholics, they compared the patterns of genetic code from each. The researchers discovered a particular set of genes was expressed together in the brain tissue of those who had consumed the most alcohol.

"This provides the most comprehensive picture to date of the gene sets that drive alcohol dependence," said Harris. He and his co-researchers hope their work will lead to better screening, possibly before a person even begins to drink, when evaluating the risk factors for alcohol dependence.

Source: Harris RA, Farris S, Mayfield RD, et al. Transcriptome organization for chronic alcohol abuse in human brain. Molecular Psychiatry. 2014.