The genetic mutations you probably didn't even know you had

You know in the X-Men films where there’s a Mutant Registration Act and anti-mutant campaigners and stuff? Those guys are jerks, not just because it’s glaringly obvious that Wolverine is cool as hell and you should want to be on his team, but because we’re all mutants.

That’s how evolution works. Genetic mutations take place and, if evolution supports them because they increase people’s chances of surviving long enough to breed, they just become a feature of a species. Mutation is essential to evolution.

Here are four of the most common mutations, none of which require ooze, Weapon X programs or irradiated post-apocalyptic wastelands to occur.

• Blue eyes

  

  Once upon a time, all humans had brown eyes. That was actually the case until fairly recently - mutations in a gene called HERC2 between 6,000 and 8,000 years ago led to the brown pigment being blocked, resulting in Frank Sinatra-style peepers. These days about 8% of the world’s population have blue eyes, and all are descended from the same common European ancestor. A male skeleton found in Spain dating from about 7,000 years ago was found to have the HERC2 mutation, so it could have been him, flashing cheeky sapphire winks all over the place and spreading his genes, if you know what we mean.

• The ability to process lactose

  

  Most mammals stop drinking milk when they stop being babies, and in fact find it difficult to process in adulthood as their production of the lactose-processing enzyme lactase slows down. Not humans, who can’t get enough of that creamy moo-juice. That wasn’t always the case though - it only happened about 10,000 years ago, somewhere around Turkey, but spread across the globe amazingly quickly. Once people could drink milk for their whole lives, pew pew pew, agriculture was invented.

• Red hair

  

  The best of all hair colours stems from a mutation in a single gene, MC1R. Only about 4% of the world has it, mainly in Northern Europe, where it’s thought to have spread either due to thriving in once-isolated communities that later spread, or honestly, just because. A byproduct of this mutation is different experiences of pain - red-haired people have a lower tolerance for thermal pain (i.e. burns), but a higher tolerance for other forms of pain like electric shocks.

• A lack of wisdom teeth

  

  Wisdom teeth, which suck, aren’t necessary for the kind of diet enjoyed by modern humans, and can’t really fit in our mouths. As humans evolved, our brains got bigger, which necessitated a narrower jaw. There wasn’t room in everyone’s mouths for the third set of molars (as wisdom teeth are also known) to come in, so huge amounts of them ended up impacted, infected and in a lot of pain. Luckily, 300,000 to 400,000 years ago, along came a handy mutation which prevented the third, unneeded molars coming in. It’s now shared by up to 25% of Europeans, 40% of Asians and, why not, 45% of Inuits. Part of how the mutation spread is the logical but slightly silly idea that it’s hard to feel horny when crippled by toothache, so people with impacted molars were less likely to breed.

(Main image: iStock)