This is a mutant. Moreover, these mutants appeared only 6,000 years ago. Don't believe me?
Now I will tell you everything …
If you trace the history of mankind, it is not difficult to find that blue eyes were especially valued at all times. We must not forget about the legendary blue eyes of Frank Sinatra, thanks to his blue eyes, Paul Newman conquered millions of women's hearts, and now this tradition in Hollywood, however, already in relation to men's hearts, continues Cameron Diaz. However, the question of how and why blue eyes appeared has always remained something of a genetic mystery, but only until now.
A team of scientists led by Hans Eiberg of the Department of Cellular and Molecular Medicine at the University of Copenhagen traced the development of a genetic mutation that led to blue eyes. This mutation occurred 6,000 to 10,000 years ago. Before this period, blue eyes did not exist.
“Originally, all humans had brown eyes,” explains Hans Eiberg.
The mutation affected the so-called OCA2 gene, which is involved in the production of melanin, the pigment responsible for the color of hair, eyes and skin.
"A genetic mutation that affected the OCA2 gene on our chromosomes created a 'switch' that literally turned off the ability to create brown eyes," says the scientist.
This genetic switch is found in a gene that is linked to OCA2. It does not completely "turn off" the gene, but restricts its activity, which reduces the production of melanin in the iris. As a result, it weakens the brown eye color to blue.
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If the OCA2 gene were completely disabled, hair, eye and skin color would be completely free of melanin, which happens in albinos.
Eiberg and his team studied DNA from mitochondria (energy-producing cellular structures) of blue-eyed people in Jordan, Denmark and Turkey. The study was conducted on women, so it could trace maternal lines.
The researchers paid particular attention to the OCA2 gene and a genetic mutation associated with stopping the production of melanin.
Over the course of several generations, segments of hereditary DNA have intermixed so that the sequence is different for everyone. However, some of these segments are not mixed, they are called haplotypes. If a group of people share long haplotypes, this means that this sequence appeared in our ancestors relatively recently. The DNA sequence didn't have enough time to shuffle.
The study was able to prove that blue-eyed people in Denmark, as well as in Jordan, have a common haplotype and they all have the same gene changes that are associated with a mutation that led to the appearance of blue eyes.
So all people with blue eyes can be considered relatives.
“Based on this, we came to the conclusion that all blue-eyed people have one common ancestor. They all inherited this switch on the same piece of DNA,”says Hans Eiberg.
This genetic disorder somehow spread across Europe to the whole world.
“But the question is, how did it happen that 10,000 years ago there was no one with blue eyes on Earth, and now 20 to 40% of Europeans are blue-eyed?” The scientist says.