Researchers say your genes decide whether you too would order a drink if your friend, sitting next to you at a bar, orders one.
Psychological scientist Helle Larsen from Radboud University in The Netherlands and her colleagues say that genetics may determine the extent to which you are influenced by social drinking cues - signals such as advertisements, drinks placed on a bar, and seeing other people around you drinking.
Drinking alcohol increases levels of dopamine - a brain chemical that causes pleasure and makes us feel good.
Research has suggested that carrying a specific form (or variant) of this gene (DRD4) may be associated with craving caused by alcohol-related cues.
The authors note, "Carrying the DRD4 7-repeat genotype may increase the risk for extensive alcohol use or abuse when spending time with heavy-drinking peers."
They conclude, "Whether or not people are wired to adapt their drinking to the choice and pace of others may partly depend on their genetic susceptibility to drinking cues."
The find is reported in Psychological Science.