“It’s not one gene, one problem,” he said. “This trait is controlled by vast numbers of genes and networks. This probably dashes water on the idea of treating alcoholism with a single pill.”
One of the best predictors of alcoholism in humans is the drinking behavior of their families. But to what extent this link can be chalked up to inherited genetics – versus a shared environment – has been poorly understood and a challenge to study: Parsing out the influence of genetics on drinking habits from other factors such as stress, boredom or peers who drink is not possible in humans.
“It’s very difficult to tease out the difference between what your genes are telling you to do and what you choose to do,” Muir said.
The results highlighted 930 genes associated with excessive drinking behavior, the vast majority of which are in genetic regulatory regions, not coding regions, as many researchers previously expected. Muir compared coding regions to a car and regulatory regions to the gas and brake pedals that determine the car’s speed.
“We all have the genes for alcoholism, but our genetic abilities to control it differ,” he said.
While the researchers stressed that the genetic complexity of alcoholism complicates potential treatments, they pinpointed the glutamate receptor signaling pathway – which can control a sense of reward in the brain – might be a possible target for treatments due to the number of alcoholism-associated genes it contains.