Barroom genetics: Triggering heavy drinking

Recovering alcoholics are generally counseled to stay away from “people, places and things”—anything, that is, that might be a cue for drinking. Bars are an especially potent trigger for the cravings that can lead to relapse.

Yet sober alcoholics vary greatly in their susceptibility to such social cues. Many appear to have no problem hanging around taverns and parties sipping club soda, and some even work as bartenders. But others—even alcoholics with years of sobriety—get a yearning every time they see even a stranger hoist a glass.

Why do some find these cues so vexing, while others appear free of temptation? Some new research points to genetics—but with a surprising twist. While it’s long been suspected that heredity plays some role in alcoholism, the new work suggests that there may be a specific genetic predisposition for being tempted by others’ drinking. If this finding holds up, it could have important implications for the prevention and treatment of alcohol addiction.

The work comes from the lab of behavioral geneticist Helle Larsen at Radboud University Nijmegen, in the Netherlands. Larsen and her colleagues actually created a fake bar for their study, complete with actors playing teetotalers, light drinkers, and indulgent drinkers. They brought more than a hundred men and women into the bar, one by one, under the pretense that they were taking a half-hour break from a completely unrelated study. These men and women would—seemingly by chance—end up chatting at the bar with one of the actors, who would either drink soda, nurse one beer or glass of wine, or toss back three or four drinks in rapid succession.

There were no teetotalers among the subjects. They typically drank about 14 drinks a week. The idea in this study was to see whether their drinking on this particular occasion was influenced by the drinking they observed in the fake bar—and more to the point, whether their actions were associated with their genetic make-up. The scientists had taken saliva samples earlier, and examined each subject’s DNA for a genetic variation already considered suspect in heavy drinking.

The results were clear and provocative. As reported on-line in the journal Psychological Science, those with the suspect gene did indeed ape the drinking habits of the person on the next bar stool, but only if that person was drinking a lot. Under that condition, the genetic “carriers” drank twice as much as those lacking the genetic variation. In other words, the bar itself didn’t trigger heavy drinking, nor did the tinkling of glasses or even normal social drinking. The only thing that made those with the unfortunate genes drink too much was seeing someone else boozing.