As per a newly conducted research, people with blue eyes share a unique common ancestor. A team from the University of Copenhagen has tracked down a genetic mutation that happened 6,000 to 10,000 years ago due to blue eyed people. Originally we all had brown eyes as said by Professor Hans Eiberg from the Department of Cellular and Molecular Medicine. A genetic mutation in the OCA2 gene affected our chromosomes which resulted in the creation of a "switch" that literally "turned off" the ability to produce brown eyes. In the gene next to OCA2, however, the genetic mutation does not turn the gene off completely, but rather limits its action to reduce melanin production in the iris, effectively thinning brown eyes to blue. A pigment called melanin is responsible for giving color to our hair, eyes and skin. The effect of altering OCA2 is very specific because if those genes are destroyed or completely deactivated, the human would not have melanin in their hair, eyes, or skin color. The absence of melanin gives birth to a condition known as albinism.
Furthermore, the variation in eye color from brown to green can be explained by the amount of melanin in the iris, but blue-eyed people have little difference in the amount of melanin in their eyes and are associated with the same ancestor. . They all inherited the same DNA changes in exactly the same places. In contrast, people with brown eyes have significant individual differences in the area of their DNA that controls melanin production. Professor Eiberg and his team studied mitochondrial DNA and compared the eye color of blue-eyed people in countries as diverse as Jordan, and Denmark. . The mutation from brown to blue does not represent a positive or negative mutation; and is one of several mutations such as hair color, baldness, freckles and blemishes that neither increase nor decrease human chances of survival, as said by Professor Eiberg. It just shows that nature is constantly shuffling the human genome, a genetic cocktail of human chromosomes and tests various changes.
