By Sudeep Chand
Science reporter, BBC News
Macaques varied in their reactions to consuming alcohol
A study has shown that having a particular gene variant causes some macaque monkeys to drink more alcohol in experiments.
The gene, known as the corticotrophin releasing factor (CRF) gene, is an important part of how we respond to everyday stress.
Sometimes it can become overactive and lead to stress-related problems such as anxiety, depression and alcoholism.
The findings may eventually lead to new treatments for alcoholism.
Writing in the Proceedings of the National Academy of Sciences (PNAS), the scientists found that some monkeys with the gene variant drank more alcohol, possibly to relieve their anxiety.
In particular the "T" form of the gene was associated with increased voluntary consumption of alcohol in drinks equivalent to the strength of strong beer.
Some were drinking "well over the limit, maybe up to four or five drinks in one hour. They're not drinking it because it's tasty, it smelt like rubbing alcohol".
"And they act much like humans do: some sleep, some are friendly, others are aggressive," said Christina Barr, from the US National Institutes of Health in Bethesda, Maryland, one of the authors of the study.
It is thought that a similar variant of the gene exists in humans but may be rare. There are also other genes that have been associated with alcoholism.
This may eventually lead to treatments that reduce the activity of these genes and the risk of alcoholism in those that carry them.