Blue Eyes & the Genetic Link to a Common Ancestor
Society has always been intrigued by the diverse range in human physical characteristics. Recent studies into the links between eye colour and genetics have discovered a link between blue eyes and a mutation which occurred some 6-10000 years ago. The study undertaken by Hans Eiberg, a Danish geneticist, has claimed to have drawn the connection between all people who have blue eyes and a linking common ancestor.
A study at the University of Copenhagen tested a series of individuals from Turkey, Denmark and Jordan. It was vital to select people from a range of ethnicities and locations in order to determine that the results would not be specific to one group of people. The results showed that 97% of people with blue eyes had the same mutation on the same chromosome. It was concluded that if blue eye mutation had been a random occurrence the area of the mutation would differ in each individual, rather than on the same place in the significant majority. This has prompted researchers to draw the link between people with blue eyes and a common ancestor They have concluded this by observing that the DNA for people with brown and green eyes greatly varies in each individual, whilst the DNA of people with blue colouration displays considerably lesser variation. From this observation the conclusion that all blue-eyed people must have a common link to an ancestor who first possessed this unique mutation was drawn. (Eiberg et al., 2008)
Whilst this discovery is no doubt intriguing, it does not go as far as to tell us why such a mutation would have occurred. There are no known advantages or disadvantages to eye colouration, and thus this discovery does not provide society with the possible answers to its purpose. However,this advance in genetics research should satisfy many individual’s curiosity about the variations in human appearances.
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by Natalia Tejs
by Natalia Tejs
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