Eye color is a pretty cool thing to think about. While technically speaking, our eyes are all the same color — melanin, which gives our eyes pigment, is naturally brown, Hans Rudolf Litchoff Eiberg, Ph.D., tells Science Daily — blue-eyed people lack melanin, which is why their eyes appear so much lighter. Awesome, right? Well, prepare to have your mind blown even more: everyone on this planet who has blue eyes is a descendant of a single ancestor. Yes, ONE person!
Blue eyes are the result of a genetic mutation, much like being a redhead, and that mutation began in a single human being. That means if you have that mutation now, the University of Copenhagen says you can trace your history back to one Danish family in particular.
In a report published in the journal Human Genetics, Dr. Eiberg revealed head and his team used “linkage analysis” to “fine-map” blue eyes. From there, they found that the recognizable genes had all come from a single parent, or haplotype. Not only was that haplotype found in a bunch of Danes, but also in people with blue eyes from the likes of Jordan and Turkey.
Dr. Eiberg and his fellow researchers also performed mitochondrial DNA analysis that helps trace maternal ancestry a mind-bogglingly way back. We’re talking hundreds of thousands of years. What they found was surprising and absolutely fascinating.
“Variation in the color of the eyes from brown to green can all be explained by the amount of melanin in the iris, but blue-eyed individuals only have a small degree of variation in the amount of melanin in their eyes,” the report reads. “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.”
Incidentally, it’s not just eye color that was inherited from this single ancestor. According to The Healthy, blue-eyed people have a higher risk of melanoma, a lower risk of vitiligo, and are more likely to enjoy some healthy competition.
