Scientists have found that a faulty gene may cause binge drinking.
Photo / Thinkstock
Scientists have found that a faulty gene may cause binge drinking.
Photo / Thinkstock
It's long been known that a penchant for alcohol may be in the genes, and scientists say they may now be a step closer to understanding why.
They have found that a faulty gene may cause binge drinking - and that mice with the mutation overwhelmingly prefer the taste of alcohol to water.
In fact, those with the faulty gene relied on alcohol to provide them with almost 85 per cent of their daily fluid intake.
Now the researchers are anxious to find out whether the same phenomenon applies in humans, as it would help develop new treatments for chronic alcohol abuse.
The gene was identified by introducing subtle changes into the DNA of the mice and looking for any that altered their preference for alcohol.
Lab animals with the normal version of the protein - known as Gabrb1 - showed no interest in alcohol.
They drank little or none of the wine-strength diluted alcohol when also offered a free choice between it and water.
But mice carrying the mutation were willing to work hard to obtain the alcoholic drink by pushing a lever and, unlike their normal counterparts, continued to do so even over long periods.
They would voluntarily consume sufficient alcohol in an hour to become intoxicated and even have difficulty in coordinating their movements.
The findings, published in the journal Nature Communications, could help identify people most at risk of developing an alcohol addiction at an early age.
Lead researcher Dr Quentin Anstee, of Newcastle University, said: "It is amazing to think a small change in the code for just one gene can have such profound effects on complex behaviours like alcohol consumption.
"We are continuing our work to establish whether the gene has a similar influence in humans, though we know in people that alcoholism is much more complicated as environmental factors come into play.
"But there is the real potential for this to guide development of better treatments for alcoholism in the future."
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The variant of Gabrb1 triggers chemicals known as GABA and GABAA that control feelings of pleasure and reward in the brain.
"The mutation is altering its structure and creating spontaneous electrical activity in the brain in this pleasure zone, the nucleus accumbens," Dr Anstee said.
"As the electrical signal from these receptors increases, so does the desire to drink to such an extent that mice will actually work to get the alcohol, for much longer than we would have expected."
Professor Howard Thomas, of Imperial College London, said: "We know from previous human studies the GABA system is involved in controlling alcohol intake.
"Our studies in mice show a particular subunit of GABAA receptor has a significant effect and most importantly the existence of these mice has allowed our collaborative group to investigate the mechanism involved. This is important when we come to try to modify this process first in mice and then in man."
