Where Do Blue Eyes Come From?
Scientists track down the genetic mutation that gives humans blue eyes.
Research completed in 2008 showed that every person with blue eyes shares a single ancestor who lived between 6,000 and 10,000 years ago.
“Everyone had brown eyes up till that point”, said Hans Eiberg from the University of Copenhagen. He and his colleagues showed that a mutation in the OCA2 gene reduced melanin production.
Enter Blue Eyed Eve
They discovered that the mutation arose in a single individual in the Near East 6,000–10,000 years ago during the neolithic period. This genetic mutation resulted in the creation of a switch, which “turned off” the ability to produce brown eyes.
The switch’s effect on OCA2 is quite specific. If the OCA2 gene had been completely destroyed or turned off, humans would not have melanin in their hair, eyes or skin color. Also known as albinism.
“Out of 800 persons we have only found one person which didn’t fit — but his eye color was blue with a single brown spot,” Eiberg said in an interview, referring to the finding that blue-eyed individuals all had the same sequence of DNA linked with melanin production.
“From this we can conclude that all blue-eyed individuals are linked to the same ancestor,” Eiberg said. “They have all inherited the same switch at exactly the same spot in their DNA.”
Image Credit: Foxnews
Reference:
Journal of Human Genetics Vol 123. Ie 2, pg. 177-87
Well, this isn’t so mindblowing to me. All evolutionary traits start with a single mutation in one being. I can’t imagine it being any other way.
Well, not every trait can be traced back to beginning in the last 10000 years! Thats evolution in action.
What about green eyes?
I read that green and hazel eyes are a dilution of brown pigment, so green eyes have always been with us, I guess!
People with green eyes are descended from gods and immortal heroes.
so that mean I can make my eyes turn blue just by switching off a gene?
I have blues eyes and my left has a brown spot too.
lol “Everyone had brown eyes up till that point” and about other colors like hazel that are not blue? is this a real study?
The adaptation of blue eyes no doubt is due to people living in the darkness of caves. No need for melanin in a cave. This is the same for lighter skin.