Scientists have identified a gene that regulates alcohol consumption which when damaged can make mice drink to excess.
The study found that while normal mice have little or no interest in alcohol, mice with a specific genetic mutation overwhelmingly chose water containing diluted ethanol to make it have roughly the same potency as wine.
They found these mice would even perform tasks to win an alcohol “reward”, and would drink so much they became inebriated.
The research, published today in Nature Communications, may help scientists develop an understanding of alcoholism in humans.
Liver expert Dr Quentin Anstee, from Newcastle University, and joint lead author said: “It’s amazing to think that 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 that in people 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.”
A consortium of researchers from five UK universities worked at the Medical Research Council’s Mammalian Genetics Unit to introduce subtle mutations into the genetic code at random throughout the genome and tested mice for alcohol preference.
This led them to identify the gene Gabrb1 which changes their preference so strongly that mice carrying either of two single base-pair point mutations in this gene preferred drinking alcohol over water.
Mice carrying the mutation were willing to work for alcohol, and drank so much they became inebriated and even have difficulty in coordinating their movements.
Scientists believed they have found the mechanism involved, and will try to modify it in mice, then in people.
Professor Hugh Perry, chair of the Medical Research Council’s Neurosciences and Mental Health Board, said: “Alcohol addiction places a huge burden on the individual, their family and wider society.
“There’s still a great deal we don’t understand about how and why consumption progresses into addiction, but the results of this long-running project suggest that, in some individuals, there may be a genetic component.
“If further research confirms that a similar mechanism is present in humans, it could help us to identify those most at risk of developing an addiction and ensure they receive the most effective treatment.”
The study is a collaboration between Imperial and University Colleges in London, and the universities of Newcastle, Sussex and Dundee.