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I think Mama's old mailman had green eyes because all of my family has blue (I mean blue!) eyes except me. I got green.
Posted on 01/30/2008 2:10:37 PM PST by decimon
New research shows that people with blue eyes have a single, common ancestor. A team at the University of Copenhagen have tracked down a genetic mutation which took place 6-10,000 years ago and is the cause of the eye colour of all blue-eyed humans alive on the planet today. What is the genetic mutation
“Originally, we all had brown eyes”, said Professor Eiberg from the Department of Cellular and Molecular Medicine. “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”. The OCA2 gene codes for the so-called P protein, which is involved in the production of melanin, the pigment that gives colour to our hair, eyes and skin. The “switch”, which is located in the gene adjacent to OCA2 does not, however, turn off the gene entirely, but rather limits its action to reducing the production of melanin in the iris – effectively “diluting” brown eyes to blue. The switch’s effect on OCA2 is very specific therefore. If the OCA2 gene had been completely destroyed or turned off, human beings would be without melanin in their hair, eyes or skin colour – a condition known as albinism. Limited genetic variation
Variation in the colour of the eyes from brown to green can all be explained by the amount of melanin in the iris, but blue-eyed individuals only have a small degree of variation in the amount of melanin in their eyes. “From this we can conclude that all blue-eyed individuals are linked to the same ancestor,” says Professor Eiberg. “They have all inherited the same switch at exactly the same spot in their DNA.” Brown-eyed individuals, by contrast, have considerable individual variation in the area of their DNA that controls melanin production.
Professor Eiberg and his team examined mitochondrial DNA and compared the eye colour of blue-eyed individuals in countries as diverse as Jordan, Denmark and Turkey. His findings are the latest in a decade of genetic research, which began in 1996, when Professor Eiberg first implicated the OCA2 gene as being responsible for eye colour. Nature shuffles our genes
The mutation of brown eyes to blue represents neither a positive nor a negative mutation. It is one of several mutations such as hair colour, baldness, freckles and beauty spots, which neither increases nor reduces a human’s chance of survival. As Professor Eiberg says, “it simply shows that nature is constantly shuffling the human genome, creating a genetic cocktail of human chromosomes and trying out different changes as it does so.”
Heh.
“Both your parents carried a recessive gene for blue eyes. They had a four in one chance of any child having blue eyes.”
I always thought both my parents were idiots growing up.
Fortunately, there was a one in five chance of them creating a genius and here I am!
:’) No one will hold it against you.
Well, at least the OTHER FREAKS won’t. ;’) ;’) ;’)
Groups isolated on islands wind up with the same last name. It’s just how it winds up. The isolation concentrates and speeds up a process that is going on everywhere, but goes on mostly invisibly. Blue eyes are just easy to spot. A similar study would show common ancestry for everyone with kinky hair, or (perhaps) a given blood type (such as B, which is the least common major bloodtype; AB people would also have their B gene on chromosome 9 tested). This blue eye study is probably not done for political purposes, but will surely be twisted into such purposes.
Genetics.
Actually, there are two types of eyes, dark and light. One of your parents probably had hazel eyes which can result in a blue eyed child. My mother and her mother had hazel eyes.
>>That has to be David Bowie’s offspring. One brown, one blue eye.....
I seem to remember Bowie saying in an interview that his eyes aren’t actually different colors. In primary school, some bully smacked David in the head with a bottle or something for talking to his girlfriend. As a result, his iris is frozen open.
I had a childhood friend who had one green and one blue eye. On top of that, his pupils were diamond or slit shaped like a cat.
Adam...Noah
3 Putins on the left, 3 Craigs on the right
(though with the KGB, you never know how many doubles Vlad may have...).
Actually, that makes them a busy girl...
Umm... Chances of survival have nothing to do with passing on genes. Chances of reproduction however... That's the ticket.
I wonder when the application form for Scientology is going to arrive.
As the only blue-eyed member of my family, I felt like a mutant. Now it’s confirmed.
In some recessive traits, being heterozygous (carrier state) infers resistance to certain infectious diseases. Examples include sickle cell anemia (malaria), cystic fibrosis (tuberculosis) and Tay-Sachs (typhoid).
I’m sorry, it is true. You’ve been taught wrong. If you want to get really technical, even the blue pigment doesn’t exist. It’s the blood vessels that create the bluish color, just as some veins close to your skin appear blue if you have very pale skin.
Humans only have two pigment variations...brown and yellow(or gold, which is dark yellow). Green exists in reptiles and birds, but not mammals.
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I think Mama's old mailman had green eyes because all of my family has blue (I mean blue!) eyes except me. I got green.
Mine are green...Parents’ are blue. Is my mama suspect?
Wouldn’t two mates have blue?
You came into this world Special Delivery?
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