Researchers and addiction specialists know that, overall, roughly half of any person’s lifelong risk for developing a physical dependence on alcohol (i.e., alcoholism) stems from the details of his or her genetic inheritance. In recent years, research teams from the U.S. and other countries have begun to identify some of the specific genes that contribute to increased odds of developing alcoholism. In a study scheduled for publication in 2014 in the journal Biological Psychiatry, researchers from several U.S. institutions outlined the newly discovered role that a gene known as Nf1 plays in boosting alcoholism risks.
The physical dependence associated with alcohol consumption leads to a range of addiction-related symptoms that can include lack of the ability to stay away from alcohol, declining susceptibility to the mind-altering effects of alcohol (i.e., rising alcohol tolerance), repeated urges or cravings for more alcohol, repeated consumption of alcohol in dangerously inappropriate situations and alcohol withdrawal, a potentially severe syndrome that arises when alcohol intake drops below the brain’s existing expectations. In the 21st century, the medical and research communities have clearly established a substantial overlap between alcoholism and diagnosable, non-dependent alcohol abuse. Current guidelines in the U.S. recognize this overlap by categorizing alcoholism and alcohol abuse under a single disease heading called alcohol use disorder. While doctors still commonly use the terms alcoholism and alcohol abuse in their daily practices, alcohol use disorder is the diagnosis that officially accounts for both conditions.
Genetic Roots of Alcoholism
The genetic roots of alcoholism are fairly complicated, the National Institute on Alcohol Abuse and Alcoholism reports. In each person, a number of genetic variations act independently or together to increase or decrease the odds that alcohol dependence will occur. Each individual’s overall risks for alcoholism are also strongly influenced by the interaction between genetic inheritance and environmental factors that exert their influence during childhood, adolescence or adulthood. A number of genes associated with alcoholism have come to light in recent years. For example, in a study published in 2014 in the journal Translational Psychiatry, a team of German and American researchers identified a grouping of 11 genes that, when present together in certain variations, help predict the onset of alcohol dependence with a reasonable degree of accuracy. In another study, published in 2014 in the journal Alcoholism: Clinical & Experimental Research, a South Korean research team concluded that more than a dozen out of 22 possible variations of a single gene, known as HTR7, help increase the odds that alcoholism will affect any given individual.
Influence of the Nf1 Gene
In the study scheduled for publication in Biological Psychiatry, researchers from institutions including The Scripps Research Institute, the University of Pennsylvania and Boston University used laboratory experiments on mice to determine the ways in which variations in the Nf1 gene influence alcoholism risks. This gene was previously identified as a potential alcoholism contributor, but no one really knew the exact role it plays in brain function. During the laboratory experiments, the researchers manipulated the Nf1 genes in the mice’s DNA and used a range of tests to determine how these manipulations affected alcohol intake. The researchers concluded that the Nf1 gene plays its part in normal health by regulating levels of a brain chemical responsible for keeping the rate of communication between the brain’s nerve cells within certain limits. They also concluded that mice with fully functional versions of this gene have a tendency to drink excessively after experiencing one or more bouts of alcohol withdrawal. In a second phase of the study, the researchers examined the variations of the Nf1 gene found in a sample pool of roughly 9,000 adults. They concluded that certain variations of the gene are linked to increased risks for developing alcoholism, as well as increased risks for experiencing particularly severe forms of the condition. The study’s authors believe their work helps explain a previously unknown pathway for the development of alcoholism. They also believe that their work will eventually contribute to an improved understanding of the disorder that, in turn, leads to the development of improved treatment options for affected individuals. Finally, the authors recommend that other research teams concentrate their efforts on clarifying the ways in which the Nf1 gene impacts basic brain function, as well as the ways in which the gene takes on forms that increase alcoholism risks.