| Blue-Eyed People Have Common Ancestor |
|
|
| Contributed by J. R. Ransom | |
 Blue Eyes According to new research, all people with blue eyes can trace their ancestry back to one person who probably lived about 10,000 years ago in the Black Sea region. Scientists studying the genetics of eye color at the University of Copenhagen found that more than 99.5% of blue-eyed people who volunteered to have their DNA analysed have the same tiny mutation in the gene that determines the color of the iris. Professor Hans Eiberg of the university said he has analysed the DNA of about 800 people with blue eyes, ranging from fair-skinned, blond-haired Scandinavians to dark-skinned, blue eyed people in Turkey and Jordon.  India's Aishwarya Rai "All of them, apart from possibly one exception, had exactly the same DNA sequence in the region of the OCA2 gene. This to me indicates very strongly that there must have been a single common ancestor of all these people." he said. Professor Eiberg said that brown is the "default" color for human eyes which results from a build-up of the dark skin pigment, melanin. However, in northern Europe a mutation arose in OCA2 that disrupted melanin production in the iris and caused the eye color to become blue. "Originally, we all had brown eyes." said Eiberg. "But a genetic mutation affecting the OCA2 gene in our chromosomes resulted in the creation of a 'switch' which literally turned off the ability to produce brown eyes."  America's Angelina Jolie The study reported in the journal Human Genetics indicates that the mutation originated in just one person who became the ancestor of all subsequent people in the world with blue eyes. "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," Eiberg was quoted as saying by The Independent of Britain on Thursday. Men and women with blue eyes have almost exactly the same genetic sequence in the part of the DNA responsible for eye color. However, brown=eyed people, by contrast, have a considerable amount of individual variation in that area of DNA. Even though the scientists are unable to pinpoint the exact date when the mutation occurred, evidences suggested it probably arose about 10,000 years ago when their was a rapid expansion of the human population in Europe as a result of the spread of agriculture from the Middle East. Visit: Times of India. |
| < Prev |
|---|
