The Hereditary Factors Behind Alcohol Addiction

Those stories about scientists discovering a gene that explains Uncle Gene’s drinking problems, there may be nuggets of truth to them. To say, however, that there is one lonely gene responsible for alcohol abuse — that’s bunk.

Genetics do play a role, though. Research shows genes contribute to approximately half the risk of developing alcohol use disorder.

Other factors — the environment we grow up in, the types of interactions we have with others — tend to make up the rest.

Or, in the nature vs. nurture argument: it’s both.

Is Alcohol Addiction Genetic?

Some people have a built-in mechanism that may make them less inclined to take up drinking. Occurring more often in Asian populations (but not exclusively), for example, is a gene variant that creates uncomfortable side effects when drinking, such as flushing, nausea, and a sped-up heartbeat.

Thus far, two genes that regulate how alcohol is metabolized seem to be the strongest indicators for alcohol dependence and addiction. Researchers are discovering other gene variants that also point toward a greater likelihood of alcohol abuse or alcoholism.

The World Health Organization (WHO) estimates that in 2016, alcohol was tied to 3 million deaths worldwide, and alcohol abuse is linked to 5.1 percent of disease globally. For those aged 15-49 years, alcohol accounts for 10 percent of deaths. Males are more affected — 7.1 percent, compared to 2.2 percent of women worldwide — by illness and death connected to alcohol abuse.

Alcohol is also linked (on a global scale) to a number of woes, including:

• 48 percent of liver cirrhosis cases
• 27 percent of traffic injuries
• 26 percent of mouth cancers
• 20 percent of tuberculosis diagnoses
• 18 percent of suicides
• 18 percent of interpersonal violence
• 7 percent of hypertensive heart disease cases

Considering lifelong risk for alcohol abuse, to the point where it would meet Diagnostic and Statistical Manual of Mental Disorders criteria, 12.5 percent of U.S. residents would qualify as alcoholics at some point in their lives, and an additional 17.8 percent would qualify as alcohol abusers.

With data like that, it’s clear to see why finding a gene responsible for alcohol abuse and dependence is so appealing.

Is Alcoholism Inherited?

Alcoholism tends to run in families, but it’s not a guarantee that it’ll plague generation after generation. The relationship between alcohol and genetics is complex, to say the least.

Genetics do seem to factor, however. Looking at adoptees, for example, if their biological parents were alcoholics, they may be more likely to abuse alcohol, but it’s not a given. With twins, too, it seems genetics plays a strong role in alcohol abuse. Lab rats and mice bred to choose alcohol and bred to have a more painful withdrawal to intoxicants reinforce the idea that alcoholic traits are rooted in genetics.

While genes definitely point toward a greater likelihood toward abuse, there is no gene solely responsible for alcoholism.

Genetics do impact some behaviors and outcomes, however, including:

• The risk for alcohol dependence
• The amount of alcohol consumed
• The likelihood of developing alcohol-linked diseases such as cirrhosis

Even though genetics influence such things, it remains unknown which variants are to blame as well as how they contribute.

Is Alcoholism Considered Hereditary?

Environment and social factors influence whether someone will overdo it or stop after one drink. The safest bet, for now, is to be aware that there are an endless combination of components, both genetic and from outside influences, that contribute to whether someone ends up a teetotaler, an occasional drinker, or an out-of-control alcoholic.

In more anecdotal cases where, for example, celebrity offspring of infamous drug and alcohol abusers, whether they’ve always been sober or whether they’re on a program, it’s hard to say if genetics or environment played a part.

Is there an Alcoholic Gene?

There’s no clear way to determine how much of someone’s genetic background contributes to alcohol dependency.

Like mentioned earlier, genes are estimated to be responsible for about 50 percent of the risk of developing an alcohol use disorder. The genes that impact how someone metabolizes intoxicants may play a key role.

In one study, scientists analyzed the genomes of 15,000 alcoholics and 38,000 non-abusers. The researchers found that people who had a specific variant of the gene that controls how the body converts alcohol to the hangover-causing chemical compound acetaldehyde were at greater risk to become dependent on alcohol. The variant slows acetaldehyde’s exit from the liver.

People who have a different variant of the gene quickly burn up the alcohol, which in turn spikes their acetaldehyde levels, leading to hangovers. Perhaps this condition could be considered a genetic predisposition to alcoholism.

One could liken the gene’s functioning to a dose of Antabuse, a drug prescribed to some alcoholics that produces nasty side effects when someone drinks intoxicants. Antabuse acts as a disrupter. It prevents the body from converting acetaldehyde into acetic acid, which causes acetaldehyde to build and unpleasant symptoms to develop.

In such an instance — where overindulging quickly becomes overly unpleasant — genetics (and science, in the case of Antabuse and other drugs that produce the same effects) may play a key role in whether someone can or can’t easily stop drinking.