Some teenagers are prone to binge-drinking because they have a variant of a particular gene, scientists have found.
Researchers at King's College London discovered a gene called RASGRF-2 plays an important role in controlling how alcohol stimulates the brain to release dopamine, which is responsible for feelings of pleasure and rewards.
They also found that a particular version of the RASGRF-2 gene ensures people gain a stronger sense of reward when they consume alcohol, making them more likely to be heavy drinkers.
The findings, which are published in the Proceedings of the National Academy of Sciences, help to explain why some teenagers are more prone to drinking alcohol than others.
Lead author Professor Gunter Schumann, from King's Institute of Psychiatry, said: 'People seek out situations which fulfil their sense of reward and make them happy, so if your brain is wired to find alcohol rewarding, you will seek it out.
'We now understand the chain of action: how our genes shape this function in our brains and how that, in turn, leads to human behaviour.'
Meanwhile, a separate study by the charity Drinkaware suggests a link between parents' drinking behaviour and their children's relationship with alcohol.