Researchers from the Department of Experimental Psychology at the University of Bristol, in collaboration with colleagues from the University of Oxford, found that the amount of beer, wine and other alcoholic drinks that people regularly consume, and possibly an individual's susceptibility to addiction, may be related to differences in genetic make-up.
Lead researcher Dr Marcus Munafò, at the Department of Experimental Psychology, University of Bristol, said: "Our study suggests that there's a genetic basis to certain kinds of behaviour, including alcohol consumption, which may be important in influencing whether people are at an increased risk of alcohol dependence. Understanding genetic influences on behaviour is important if we are to understand why some people are more likely to become addicted than others."
The scientists analysed data from almost a thousand people who gave detailed information on their drinking habits. The research focused on a key gene that controls chemical signalling in the brain. Different versions of this gene may affect the balance and effect of signalling molecules and in turn help to shape individual drinking habits.
Scientists do not know precisely why particular genetic variants may influence behaviour, but they do have a few clues. They found that one particular genetic variant - a version of the dopamine D2 receptor gene (DRD2) - was strongly associated with alcohol consumption.
The DRD2 gene appears to influence the 'high' that people derive from drugs such as alcohol. People without this variant might derive less pleasure from alcohol, and may therefore drink less.
The large-scale study, published in The Pharmacogenomics Journal [March 2005], provides evidence that particular human genes can influence behaviour. It is being hailed as an important advance in understanding why some of us drink more than others, and why some people might be more vulnerable to alcohol dependence.