Alcohol dependency linked to ‘bad’ gene


Ekaterina Tithoniouk reports of a new study that might lead to a cure for alcoholism

In modern day Ireland, it is often difficult to personally realise the boundary between a few hearty drinks, and full-blown alcohol abuse. People who regularly drink heavily develop a reliance on alcohol for every-day functioning. Alcoholism is typically defined as physical dependence on alcohol, to the extent that stopping alcohol use will bring on withdrawal symptoms.


alcoholismThis so-called ‘scourge of humanity’ has existed ever since the first Stone Age people figured out how to ferment ale, and has remained with us for thousands of years. The ancient Egyptians fermented grapes into wine, while the Incas spat chewed corn into a tub, left it for three days, and then got intoxicated from the resulting brew – and of course, alcoholism advanced hand-in-hand with these developments.

Throughout the ages, there have been many methods thought up to combat alcohol abuse, ranging from public whipping to flamboyant exorcisms of the demons living within the person, to more modern methods of group therapy and rehabilitation clinics.

Alcoholism was regarded, until most recently, as a craving that could only be beaten with a ‘mind-over-matter’ approach, emphasising willpower and learning control. It was believed to be an addiction that could happen to anyone, regardless of heredity features or family background.

But a growing body of scientific evidence proves that alcoholism has a genetic component. An individual’s risk of becoming dependant on alcohol is influenced by a hereditary gene, identified as GABRG3 on chromosome 15 of a person’s DNA.

A study run by investigators at the Washington University School of Medicine is the first to link this particular gene to alcohol dependence. Taking interviews and DNA samples from more than 10,000 individuals in alcohol treatment centres, as well as from their families, the survey succeeded to link small genetic defects in the gene GABRG3 to an increased likelihood of an individual to develop alcoholism.

This new research reinforces many other studies that have used laboratory animals, as well as human test subjects, to illustrate the role of genes in the growth of alcoholism. The most famous of these is a twin study in Sweden, recording alcohol use in twins who were adopted and reared apart. The incidence of alcoholism was only slightly higher in individuals who were exposed to alcoholism by their adoptive families; however alcohol dependency was drastically higher among the twins whose biological parents were alcoholics, regardless of whether their adoptive parents drank or not.

These tests indicate that genetic factors play a huge role in the development of alcoholism. According to the American Academy of Child and Adolescent Psychiatry, children of alcoholics are four times more likely than other children to become alcoholics.

Alcoholism is a growing problem, especially in such countries as Ireland, Finland and the UK, where extreme binge drinking is prevalent. Currently 38 per cent of Irish drinkers binge drink, compared to a European average of ten per cent. The Irish also have the highest levels of alcohol consumption per capita in all of Europe, and it is estimated that 5.5 per cent of us have an alcohol abuse problem.

Dependency on alcohol is prevalent among young adults, especially in students overindulging in their consumption of this drug. As with many other drugs, repeated abuse can lead to severe addiction. One result of prolonged use is an increased tolerance for alcohol, so that larger quantities need to be ingested in order for the individual to become intoxicated. Another result is the appearance of withdrawal symptoms, where the individual feels an overpowering urge to drink in order to alleviate their distress.

Although this groundbreaking research has cast a ray of light on the possible causes of alcoholism, there are many more questions left to solve, such as the possibility of a medical cure. A decade ago the notion of curing alcoholism would have sounded almost ridiculous, but in light of these recent breakthroughs, it seems more and more plausible in the years ahead.