My dad was 18 when he first set off to explore the world on his own. And even then, he'd already seen a fair portion of it. He'd lived with his parents in Hong Kong and Singapore. He'd been to school in Australia and in Scotland.
But when he was 18 he took the biggest leap of faith: he signed up to work as an apprentice in the merchant navy. He took a two-year contract with a shipping company. He walked up the gangplank of a ship he'd never boarded before, to do a job he'd never performed, with a bunch of people he'd never met, to see a world he'd never experienced, knowing he wouldn't return home for two years at the least. In fact, he didn't make it back for four.
My mum, meanwhile, says she never had much interest in travel. That is, until she decided, at the age of 19, to leave her home in England, to jump on board a ship and sail to the Bahamas. She'd find work when she arrived, she figured. She'd sort something out.
She says she never had much interest in travel, but that move is the sort you would only make with the heart of an adventurer, particularly back then when you couldn't just jump on a plane and fly home if things went wrong. She stayed in the Bahamas for a few years before moving to Australia, where she eventually got a job on a cruise ship in order to see more of the world.
My parents still travel, constantly. They're both wanderers, both explorers. Dad has visited pretty much every country with a coastline. Mum still hikes up mountains. She went sky-diving when she was in her 60s. They've both been to Antarctica. They've camped in Utah. They've hung out in Buenos Aires.
I mention all of this by way of explanation. See, I don't remember getting the "travel bug", as some travellers do. I can't pinpoint a particular moment when I realised that I loved travel, that it was all I ever wanted to do. I've just always known. I've always wanted to do it.
And that's because of my parents. Not just because of the way they brought me up, or the experiences they gave me, but possibly, in an even larger way, because of their genes, because of a special genetic variation that they most likely possess, and that they most likely passed on to me.
It's called the "wanderlust gene". They probably have it. I probably have it. You might have it too.
Scientists have discovered a genetic variation called DRD4-7R, which occurs in about 20 per cent of the human population. This variation affects dopamine levels in the brain – and dopamine isn't just a chemical that makes you feel good, as is commonly understood. It also makes you more curious, more obsessed with finding things that are new and interesting and exciting, more likely to take risks in the pursuit of pleasure.
Sound familiar? Thrill-seekers probably have DRD4-7R. Inventors probably have it too. And, of course, travellers have it. This genetic variation fills you with wanderlust. It gives you the bug.
You probably know, already, if you have DRD4-7R. I'm sure I do. Even now, after visiting 90-odd countries and finding a career that allows me to travel constantly, I still feel jealous when I see a plane taking off, carrying all of those people somewhere amazing. I still get a thrill from staring out of the window as my own flight departs. Even the taxi ride to the airport is exciting.
If this thing is real, then I'm very likely to have it.
There are, however, other explanations for the urge to explore than genetics. The wanderlust gene isn't a settled science, but an interesting theory, something certain scientists and psychologists believe is true – but there could be more factors at play than the existence of DRD4-7R.
Nurture still has a lot to do with your attitude towards travel. Your parents' genetics might affect your wanderlust, but their habits when you were young doubtless also have a huge impact.
If you travelled a lot as a child, you're more likely to continue that behaviour into adulthood. Similarly, if you were encouraged to dream of exploration as a kid, to imagine life outside the confines of your own world, to play and to aspire to curiosity, then you're more likely to become a travel obsessive later on in life.
And even if you had none of those things, you could still quite easily fall in love with the life of a wanderer. Plenty of people do at all different stages of their lives. Sometimes it's a person you meet that inspires your passion, a partner or a good friend that draws you into travel obsession. Other times it's just the lack of anything better to do that forces you out of your comfort zone and into the life of a explorer.
For those of us who've always felt that way, however, the explanation could be in our genes.
Do you think you have the "wanderlust gene"? Or did your love of travel come from somewhere else?
- See also: The 10 countries every true traveller should have already visited
- See also: Science proves that travel is the secret to happiness
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