Alcohol Consumption and Genetics
Scientists have found that the genes which influence the amount of alcohol people drink may be distinct from those that affect the risk of alcoholism.
A large number of studies have focused on a genetic predisposition to alcoholism. They presume that the genes involved in this disorder, combined with environmental factors, influence susceptibility to alcohol dependence.
The various genetic pathways affecting alcohol drinking behavior have been investigated by Dr. Boris Tabakoff and his team at the University of Colorado-Denver using both rats and humans.
They compared genes involved in alcohol pathways in rats with human genes, using male study participants from Montreal, Canada and Sydney, Australia, to identify common genetic factors across species. Alcohol consumption among the participants ranged from abstinence to heavy intake, and drinking patterns were recorded.
The researchers discovered that drinking behavior is linked to the “pleasure and reward” pathways in the brain, and also to some of the systems that control food intake. In the journal BMC Biology, they write that the results emphasize the importance of looking at signaling pathways rather than single genes, and show cross-species similarities in predisposition to alcohol consumption.
“Our results also suggest that different genetic factors predispose to alcohol dependence versus alcohol consumption,” they add.
Dr. Tabakoff said, “We know that high levels of alcohol consumption can increase the risk of becoming alcohol dependent in those who have a genetic makeup that predisposes to dependence. This is a case of interaction between genes and environment.
“Indeed, in our study we found that higher alcohol consumption in humans was positively correlated with alcohol dependence. However, because different sets of genes seem to influence the level of alcohol consumption, as opposed to propensity for alcohol dependence, we are confronted with great variation in humans.”