People are just noticing that all green-eyed people all share something in common…and it’s not just having green eyes!
If you are in possession of a pair of green eyes (your own eyes, not someone else’s, just to clarify) you are the proud owner of the rarest eye color in the world.
However, there is one thing that ties all green-eyed people together.
Some of the world’s best loved celebrities have green eyes, including; Rihanna, Paul Rudd, Scarlett Johansson, Emma Stone, Tom Cruise and Drew Barrymore.
Remarkably, only two per cent of the world’s population have green eyes.
Having green eyes, similar to blue eyes, hints at a genetic mutation. In fact, a paper published in the European Journal of Human Genetics in 2013 states that certain individuals, described as ‘homozygous,’ are more likely to have green eyes.
The European Journal paper states: “Eye colour is a feature that may fall under multiple selection pressures, including sexual, cultural, and environmental factors (ie, the level of sunlight).”
What makes blue-eyed people unique?
Despite being far more common (between eight and 10 per cent of the world’s population have them) blue-eyed people also share a unique trait.
Legendary Rat Pack singer and movie star Frank Sinatra, famously, was known as ‘old blue eyes’, while actor Alec Baldwin is well known for his piercing blue peepers, with them being regularly referenced during his multiple-Emmy Award winning turn in NBC sitcom 30 Rock.
Blue eyes are more sensitive to light. By having less melanin, blue-eyed people may squint more in daylight or require sunglasses to avoid discomfort, making photophobia surprisingly common among them.
While this may sound negative, there are many positives to this color.
A study by Louisville University professor Joanna Rowe discovered that those of us with blue eyes are more likely to be better strategic thinkers, as reported by the Daily Mail.
Professor Rowe clarifies: “It is just observed rather than explained. There’s no scientific answer yet.”
Many well known figures with blue eyes have bright minds, including Stephen Hawking, Alexander Fleming, and Marie Curie.
Most interestingly, all blue-eyed people have one particular thing in common. And no, it’s not just having blue eyes.
Blue eyes are the second most popular eye color in the world, and the shade is believed to have originated around 6,000 to 10,000 years ago.
The widespread iris coloration reportedly started thanks to a genetic mutation, which leads all blue eyed people back to the Black Sea and, in particular Ukraine.
All humans started with the same eye color
Originally, all humans had brown eyes – in different shades.
A gene was recently identified that causes blue eyes, and it’s called HERC2.
This gene switches off OCA2, which results in different shades of brown eyes, and determines the amount of brown pigment melanin we make.
Professor Hans Eiberg, from the University of Copenhagen’s Department of Cellular and Molecular Medicine, explained: “Originally, we all had brown eyes. But a genetic mutation affecting the OCA2 gene in our chromosomes resulted in the creation of a ‘switch,’ which literally ‘turned off’ the ability to produce brown eyes.”
This genetic mutation is believed to have originated from humans migrating from Africa to Europe, The Independent explains.
The University of Copenhagen study suggests that all blue-eyed people are descendants of one person. Although it has, understandably, never been discovered who this one blue-eyed being was.
In the report, Professor Eiberg says that the research into the genetic mutation of people with blue eyes ‘simply shows that nature is constantly shuffling the human genome, creating a genetic cocktail of human chromosomes and trying out different changes as it does so.’
What one thing do all green-eyed people share?
Similarly to blue-eyed humans, people with green eyes can trace their ancestry back to one region, albeit a slightly different one.
Green eyes, in fact, originate out of Siberia, in northern Russia.
The science behind these origins points to green eyes being found in Siberians approximately 2,000 years ago, during the Bronze Age.
Fast forward to the present day, and people belonging to the Caucasus region – parts of Russia, Georgia, Armenia and Azerbaijan – are more likely to be born with green eyes than someone living in a different region of the world.
According to the aforementioned European Journal’s paper, the study states: “Furthermore, homozygous individuals for the same haplotype have a different probability to develop green/grey iris colour depending on the region in which they live (ie, a person belonging to the Caucasus region has an higher probability as compared with individuals living in Central Asia).
“An explanation for these findings is the possible presence of population-specific polymorphisms that might interact with HERC2 and OCA2 genes and thus contribute to the phenotypes.
“These polymorphisms could have a higher frequency in the Caucasus region because of a different history of gene flow between the various populations.”
See, it’s just a simple case of polymorphims having a higher frequency. I knew all that before even reading the study. Honestly.
