We all know someone who seems to be constantly travelling. Their Instagram feed is populated almost exclusively by photos of them kayaking across Canadian lakes, leaping into the air on tropical beaches, climbing mountains in Nepal and swinging in a hammock in the Amazon. When they do come home, they take on a job for six months or a year – just enough time to save for their next adventure – before jetting off again. They’re afflicted, they would be the first to tell you, with a serious case of wanderlust.

But why do some people have perpetually itchy feet, while others prefer to stay firmly in one place? According to some scientists, our propensity for adventurousness could be down to genetics.

The so-called ‘wanderlust gene’ is actually a genetic variation (or allele) called DRD4-7R, which occurs in about 20% of the human population. Researchers believe that people with the DRD4-7R gene have a lower sensitivity to dopamine, the pleasurable chemical that can be triggered by anything from chocolate to ecstasy.

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As a result, these people are thought to be more likely to seek out experiences that will give them a hit of dopamine. In theory, they’re curious, adventurous and thrill-seeking, and more likely to take risks as they pursue pleasure – such as embarking on round-the-world backpacking trips or bungee-jumping off a waterfall.

The idea that there is a relationship between DRD4-7R and adventurousness is a fascinating one, and the connection was backed up by several scientific studies in the Nineties. A 2008 meta-analysis of 36 published studies on the subject, meanwhile, concluded that “the DRD4 gene may be associated with measures of novelty seeking and impulsivity”.

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Dr Richard Paul Ebstein, professor of psychology at the National University of Singapore, recently spoke to The Telegraph about DRD4-7R. He has been studying the gene for more than 20 years, and says that he believes it is definitely connected to “novelty seeking or extraverted behaviour”.

“I think overall the story is coherent,” Dr Ebstein says, adding that there is also evidence to suggest that DRD4-7R could lead people to be more impulsive and “risk prone” in financial situations.

However, the ‘wanderlust gene’ remains a point of contention in the scientific community, and many researchers warn that we should resist the temptation to attribute entire personality traits to one genetic variant. After all, there are many environmental reasons why someone might get bitten by the travel bug.

“Genes are like ingredients in a recipe – certain genes make a contribution but there isn’t one single gene for, say, wanderlust,” says science writer and developmental biologist Dr Kat Arney. “Even something like eye colour is not down to one gene.”

She concludes: “It’s not what you’ve got, it’s what you do with it that counts.”

Strangely, we find that quite uplifting. Now, where did we put that travel planner…?

Images: Pexels; iStock