Does Hereditary Play A Role In Alcoholism?

 

The pain of alcoholism is not just the addict's burden to bear, but also the weight carried by their loved ones...

                                          - Anonymous

Alcohol Use Disorder, also known as AUD, is a chronic disease described as the inability to limit one's consumption of alcohol despite adverse consequences. It is, in many instances, the cause of serious physical, emotional, and social problems. Perhaps among the most frequent questions regarding the development of AUD is how heredity factors into it.

IS HEREDITY ALONE A MAJOR CONTRIBUTOR TO ALCOHOLISM OR ARE THERE MORE?

Heredity definitely is a major contributor to the alcohol gene transfer, but there are several other causes for the development of AUD.

The Genetic Factor

Scientific studies have, for a long time, indicated that there is a genetic contribution to the risk for developing alcohol use disorder. In fact, research indicates that genes account for about half of the risk for AUD. It does not indicate that there is any single "alcoholism gene," but rather that multiple genes can combine to influence vulnerability. These genes may impact biological processes varying from how alcohol gets processed in an individual's body to the activities of neurotransmitting systems in the brain and even behavioral traits of a person.

Family History and AUD

The evidence that AUD often aggregates in families is one of the strongest indications of genetic association. People whose close relatives—for instance, parents or siblings—had issues with alcoholism themselves are more likely to face the disorder. It means that the trend of incidence within a family is informative regarding familial factors contributing to the risk of AUD. This is further supported by twin studies, which find that identical twins with the exact same genetic makeup are more likely to develop AUD compared to fraternal twins who share approximately half their genes.

How Genes Contribute to AUD

Genes can contribute to AUD vulnerability in several ways. Some genes may increase the risk through an impact on the reward system of the brain. As an example, genetic variation in dopamine receptors and transporters may alter the rewarding effects of alcohol, while other genes may contribute to individual differences in how alcohol is metabolized in the body. For example, some gene variants found in people of Asian descent can result in the build-up of acetaldehyde, a toxic by-product of alcohol metabolism. This causes unpleasant symptoms such as flushing, nausea, and a racing heartbeat when they consume alcohol. As such, most people with this gene variant tend to avoid alcohol, thus reducing their risk of AUD.

The Role of Environment

While the genes are very highly associated with vulnerability to alcoholism, they do not act alone. Environmental factors also play a role in AUD. One's rearing, social environment, peer pressure, and an early introduction to alcohol use may all impact drinking behavior. For example, individuals brought up in a family with a heavy drinking background or, on the other hand, with no parental controls at all, stand a good chance of developing AUD.

Gene-Environment Interaction

In considering the risk for AUD, the interplay between genetic and environmental factors comes into play. A person's genes may put them at risk for alcoholism, but environmental factors often determine whether this becomes a living, breathing condition. For example, someone who is genetically predisposed to AUD may never develop the disorder should they grow up in an environment that deters heavy drinking or has strong social support.

Neuroimaging Studies

Neuroimaging studies have provided insights into the structural and functional brain changes associated with AUD. For instance, individuals with AUD often show reduced volume in brain regions involved in decision-making, impulse control, and emotional regulation. Genetic factors can influence these brain changes, further elucidating the link between heredity and alcoholism.

Epigenetics and AUD

Recent epigenetic studies bring more insight into the gene-environment interaction underlying AUD. Epigenetics is generally understood as changes in gene expression, without sequence changes of the DNA itself; however, the formation is influenced by environmental factors. For instance, chronic alcohol consumption can induce epigenetic changes that have gene targets associated with addiction and could, therefore, increase the risk of AUD in the offspring.

To summarize the main points, heredity does play a major role in increasing the risk of developing alcohol use disorder, it is certainly not the only reason. One-half of the risk is genetic, and several genes contribute to vulnerability. It is very important to understand that environmental influences and gene-environment interactions are critical in determining whether or not someone develops AUD. The two will help in understanding the complex interplay between genetic predisposition and environmental factors when developing more efficient ways to prevent alcoholism and tailor-made treatments. This way, by recognizing the genetic basis of AUD, we can further empower individuals and families dealing with this relentlessly difficult condition.

Always remember that alcoholism is temporary fun with permanent damage. 

Aiana...