Alcoholism can be traced back to genetics since ancient times and with the advancement of genetic screening techniques and technology in recent decades, these hypotheses can finally be put to the test. Utilizing proven methods of case-control study, population study, and family study, researchers have been able to identify numerous genes that may contribute to alcoholism.
How are risk factor genes identified ?
Several methods are used to narrow new risk factors genes.
Case-Control: This method is the simplest to set up, it compares the genetic makeup of alcoholics and nonalcoholics.
Family: Family studies are a lot more complicated to set up, the simplest family studies require a minimum of three family members. The benefits of this method avoid incomplete ethnic and population variables. Allele variants of the same genes affect a different trait in different families and can be more easily identified.
When both of these methods point to a single gene, it is strong evidence that the candidate’s genetic makeups can strongly contribute to the development of alcoholism.
What type of Genes Contribute to alcoholism?
Genes are the instruction codes to make proteins that serve several functions in the body, such as speeding up reactions, transporting molecules or simply for structural support. There are two major types of genes that researchers look for.
Genes that encode key enzymes that are active in alcohol metabolism. For example, Does your face flush red when drinking alcohol? A variant of the ALDH2*2 gene may be responsible. Researchers found that a gene common in East Asians produce enzymes that breaks down alcohol more efficiently. This leads to 10x higher toxic build up in the body. The experience is generally unpleasant for the drinker, which greatly lowers the risk of alcohol dependence.
Genes that are involved in brain signaling such as neurotransmitters. A well studied gene would be GABRG1 that encodes for a subunit of the GABA-A receptor. This receptor is associated with signals related to addiction, identifying the exact function of the gene linked to alcohol dependence.
Many other genes that fall under those two categories are currently being studied. More tests are needed to confirm research findings.
Although great advancements have been made to identify alcoholism risk factors, the task of identifying and testing gene variants has proved challenging. However there is enough evidence to conclude genetics play a major role in how the body metabolises and receives alcohol. These traits are hereditary, so a family history of alcohol dependency would be the first indicator for the presence of risk factor genes.
Do you have family members or a loved one that suffers from alcohol dependency? If so and you would like more information on it, watch this video with Dr. Ehsan and Dr. Carlos
Genes Contributing to the Development of Alcoholism
Edenberg, H. J. (2012). Genes contributing to the development of alcoholism: An overview. Alcohol Research : Current Reviews, 34(3), 336–338.
The Genetics of Alcoholism
"The Genetics of Alcoholism." The Genetics of Alcoholism-Alcohol Alert No. 18-1992. N.p., n.d. Web. 15 Mar. 2016.