Hey, Where are you from Blue eyes?
By zteve t evans
Human eyes range in color from very dark brown to the palest of blue and is affected by the amounts of a pigment called melanin in the iris. The perception of eye color can also be affected by the prevailing light conditions and the local environment. At Copenhagen University researchers have done a lot of thinking and a lot of research on where people got their blue eyes from and come up with an answer and published their findings in Journal of Human Genetics.
All blue-eyed people are related
They have discovered that blues eyes are the result of a single mutation that happened to one person who probably lived some where in what is now Romania around the Black Sea region, around 6,000 to 10,000 years ago. This means that all blue-eyed people in the world today are genetically related to that person and each other.
According to their research, a gene in the chromosome known as OCA2 under went a mutation and can be traced back to one of our ancestors who lived in that region at that time. The researchers say that before this event every one in the world had brown eyes.
The mutation
Researcher, Dr. Hans Eiberg says, “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,” His team looked at people with blue eyes from Denmark, Jordan and Turkey and found that the genetic difference could be tracked back to the maternal lineage.
Around the world the brown melanin pigment is dominant and people with brown eyes are in the majority. Eiberg’s research shows that this mutation, for reasons unknown, seemed to affect mostly Europeans though it occurred to a lesser degree elsewhere. This distinguished them from the vast majority of people.
They have discovered that blues eyes are the result of a single mutation that happened to one person who probably lived some where in what is now Romania around the Black Sea region, around 6,000 to 10,000 years ago. This means that all blue-eyed people in the world today are genetically related to that person and each other.
According to their research, a gene in the chromosome known as OCA2 under went a mutation and can be traced back to one of our ancestors who lived in that region at that time. The researchers say that before this event every one in the world had brown eyes.
The mutation
Researcher, Dr. Hans Eiberg says, “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,” His team looked at people with blue eyes from Denmark, Jordan and Turkey and found that the genetic difference could be tracked back to the maternal lineage.
Around the world the brown melanin pigment is dominant and people with brown eyes are in the majority. Eiberg’s research shows that this mutation, for reasons unknown, seemed to affect mostly Europeans though it occurred to a lesser degree elsewhere. This distinguished them from the vast majority of people.
The first blue eyes
Odd as it may seem the first person who the mutation occurred in would not have had blue eyes and neither would their children. It would not have shown until their grandchildren or great grandchildren, or until their descendants bred together. This is because to get blue eyes they would have needed to inherit the gene from both parents.
The reasons why it spread are also unknown. Some experts think that as Europe was being colonized from Africa at the time it may have had some advantage linked to it. It may have suited the environmental differences such as amounts of sunlight or it may have bee that they were considered more attractive due to their uniqueness. Another theory is that they simply produced more children, but no one can say for certain at the moment.
© 04/07/2013 zteve t evans
Odd as it may seem the first person who the mutation occurred in would not have had blue eyes and neither would their children. It would not have shown until their grandchildren or great grandchildren, or until their descendants bred together. This is because to get blue eyes they would have needed to inherit the gene from both parents.
The reasons why it spread are also unknown. Some experts think that as Europe was being colonized from Africa at the time it may have had some advantage linked to it. It may have suited the environmental differences such as amounts of sunlight or it may have bee that they were considered more attractive due to their uniqueness. Another theory is that they simply produced more children, but no one can say for certain at the moment.
© 04/07/2013 zteve t evans
References and attributions
Copyright ztevetevans July 04th, 2013
Copyright ztevetevans July 04th, 2013