Binge drinking could be down to genes, as some people have a mutation in their DNA which makes them crave booze more, say scientists.
And this urge could spread as couples with the ADH1B gene pair up based on how much they enjoy alcohol.
Researchers at Bristol University Medical School believe this will increase the number of heavy drinkers in the future.
Dr Laurence Howe said: “Our findings suggest that alcohol behaviour directly influences mate selection.”
The team studied the genes of 47,549 couples on the UK Biobank database.
Researchers found how much someone drinks depends on whether they had the mutation or not.
If one person enjoys a tipple, the chances are their partner does, too.
The genetic mutation is also more common among Europeans than people from other continents.
Those who have it also spend less time in education, while lovers tend to match in height, education, blood pressure and even chronic diseases.
Earlier studies have found alcoholism is as much as 50% down to someone’s genes.