Blue eyes are the result of a mutation

Scientists are still only guessing when a mutation occurred, and the person had blue eyes, but some signs indicate that, most likely, it happened several decades ago. During this period there was a massive population of Europe, as agriculture from the Middle East began to spread to European countries.

Origin

The Human Genetics magazine posted a note by scientists that the mutation that caused the appearance of blue- tinted eyes most likely occurred in the northwest of the Black Sea region.

Professor Eyberg noted that "by default" the color of human eyes should be brown. Dark blue eyes are the result of a mutation, because the dark skin pigment is melanin, it affects the appearance of brown-eyed babies. However, in Northern Europe, the OCA2 gene underwent changes that disrupted the production of melanin in the iris, which led to the appearance of a blue color.

Professor Eyberg noted that all eyes had brown eyes at first, but the mutation in our chromosomes of the OCA2 gene caused a "transformation" that "turned off" people's ability to produce brown.

In the iris, the amount of melanin varies, so the brown shades are different. Blue eyes have people who had a common ancestor who changed the gene. They all inherited the same mutation of their DNA.

Blue-eyed men and women have an almost identical genetic sequence of that part of the DNA molecule that is responsible for eye color.

Prof. Eyberg conducted DNA analysis of more than 800 people, from white Scandinavian blondes to people with dark skin, but with blue eyes living in Turkey and Jordan. His experiment confirmed the hypothesis of a single common ancestor.

It is unclear why the blue eyes are more common among the population of the South of Russia and Northern Europe. Previously it was assumed that this feature gives some advantage in summer white nights or in winter polar. Perhaps this is considered more attractive and, therefore, the most favorable for sexual selection.

Features

Anatomically, the iris includes the ectoderm and mesodermal layer. On how the pigment is distributed in them, and the color depends. Chromatophores are distributed in the mesodermal layer, they contain melanin. The back layer contains many pigment cells filled with fuscin. Fibers and vessels of the iris also play a role.

The main light colors are blue, blue and gray.

The ectodermal layer is characterized by a dark blue color. If the outer fibers of the iris have a low density and low melanin content, high-frequency light is absorbed by the mesodermal layer, and low-frequency light is reflected from it. Blue eyes are the result of this refraction.

There are people who dream of changing their natural color to blue. They believe that a look at the same time will acquire beauty, depth and richness. Most often, blue eyes are attractive, photos of blue-eyed people can be decorated using some programs, in particular, photoshop. After experimenting with computer effects, you can pick up your makeup and proper makeup.