Every blue-eyed person on Earth is a descendant of one single person, scientists find

It's no secret that blue eyes are rarer than brown, but scientists have now shed light on how blue eyes came to be in the first place.

It turns out all blue-eyed people all share an ancestor, which is knowledge I'm sure will make the other blue-eyed people you're trying to pull incredibly uncomfortable.

From the little we learned during our Additional Science GCSE, we know that blue eyes are a recessive gene, meaning that you need to have two of them for the colour to become apparent.

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But, if you were wondering where exactly these genes came from, one study has found it can all be traced to one person.

We know that blue eyes are much rarer than brown eyes, with Healthline estimating that between 8 and 10 percent of the world's population have blue eyes.

And now its rarity makes sense, as scientists revealed that the genetic mutation came from a singular human who lived between 6,000 and 10,000 years ago.

Researchers have tried to discover what caused this change by studying the OCA2 gene, which determines the level of brown pigment in the human eye, for many years.

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However, it turns out that the genetic mutation that results in blue eyes is from an entirely different gene called HERC2, which completely turns off the OCA2, and 'dilutes' brown into blue.

And, how do they know that it all links back to a common ancestor? Because every single blue-eyed person has the same mutation.

Although there’s still a lot more research that needs to be done, it’s thought that the mutation could have spread when humans migrated from Africa to Europe, which would go some way to explaining why mainly people of European descent seemingly have blue eyes.

The discovery was actually made back in 2008 when a research team from the University of Copenhagen initially tracked down the mutation.

The study also looked at the variation in other less common eye colours, such as green, which further proved the idea of one person originating the blue-eyed gene.

Author of the study, Professor Hans Eiberg from the Department of Cellular and Molecular Medicine, told Science Daily: "Meanwhile, people who have green eyes can be explained by the fact they have a reduced amount of melanin in the iris, which is very different to those with blue eyes.

"From this, we can conclude that all blue-eyed individuals are linked to the same ancestor. They have all inherited the same switch at exactly the same spot in their DNA," he concluded.