A faulty gene may be a reason why people become alcoholics, a study has shown.
 

Researchers, including a team from the University of Sussex, have found
mice which have the mutation overwhelmingly preferred drinking alcohol to water.
 

The study showed normal mice showed no interest in alcohol and drink little or no alcohol when offered a free choice between a bottle of water and a bottle of diluted alcohol.
 

However, 85% of the fluid intake among mice with the damaged isolated
gene, called Gabrb1, was alcohol.
 

The researchers come from Sussex, Imperial College London, Newcastle
University, University College London, the University of Dundee and the
Medical Research Council and the Mammalian Genetics Unit in Oxfordshire.
 

University of Sussex psychologist Professor Dai Stephens is leading a
team working on how chemical receptors in the brain influence drug abuse.
 

He said: “Why some people abuse alcohol while others are readily able to control their drinking is still something of a mystery for science.
 

“This research shows that really subtle changes that can arise quite
spontaneously in a gene can have catastrophic effects on normal biological
function, and precipitate excessive drinking.”
 

Working at the genetics unit, scientists introduced subtle mutations into
the genetic code at random throughout the genome and tested mice for
alcohol preference.
 

This led the researchers to identify the gene Gabrb, which changes alcohol
preference so strongly that mice carrying either of two mutations in
this gene preferred drinking alcohol over water.
 

The group showed that mice carrying this mutation were willing to work
to obtain the alcohol-containing drink by pushing a lever and, unlike normal
mice, 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.
 

Prof Stephens said: “While it is unlikely that the identical genetic fault is a major cause of human alcohol abuse, this research indicates that
when certain receptors become leaky, the ability to know when to stop
drinking seems impaired.
 

“Unfortunately, no drugs are available at present that could reduce the
leakiness of the particular receptors involved, without dangerous side
effects from interfering with other related receptors.
 

“That might be an obvious target for future work.”