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.
“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…
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.
This isn’t a positive or negative mutation, of course. Not that the fact will prevent the ignorant from value judgements.
Like, how you interpret the headline for this post.
#6, moss,
… the blue-eyed DNA originated in Afghanistan.
Funny, I don’t feel very Talibanish. I do like opium though.
I like sex with blonde mutants.
Nobody else noticed the dual meaning of the title? Crazy, I read it one way the first time, another way the second, without even thinking about it. WEEEIRDDD..
How does this make sense. Blue eyes are recessive. So if one guy gets the mutation.. and the person he has kids with doesn’t (or she has it and he doesn’t).. they should be wiped out in that generation right? what am I missing?
Ve are zee Master Mutation Race! Today Escondido…tomorrow zee Vorld!
#36, OM
Ya think so ??? Just wait until you get to Bumfusk Utah. Once you meet James Hill in his frilly pink undies you’ll high tail it back to the civilized world.
#35–greenwood==you ask “they should be wiped out in that generation right? what am I missing.”
Well, they aren’t wiped out in a generation so your understanding of how recessive genes works is objectively speaking incorrect? And that is what you are missing. The gene for blue eyes is recessive meaning it is in the genes but not expressed until it matches up with another recessive gene. You might review the work of Mendel on how to make yellow peas?
Bobbo,
Someone’s understanding is clearly incorrect but it is not necessarily mine. The problem with your response is that it works ONLY if there is someone else out there with the recessive gene (as you said until it matches up with another recessive gene)… but if there is a single person with this mutation.. how would anyone else have the recessive gene. If you presume a single common ancestor as the article claims that had the gene and he mates with someone else who would have both dominant genes their offspring should have brown eyes. Then even if that offspring carries the recessive gene the only other possible mates (assuming no incest) would have only the dominant genes. Eventually, the gene would dissapear unless it was very consistantly passed on as recessive and started to resurface down the line with others from the same downline. The only explanation that makes sense to me is that it wasn’t limited to a single individual.
Mom was a blue eyed blond and Dad was dark haired and amber brown eyes. I am blond with deep blue eyes and have two brothers with lesser blue and less blond but still blond hair with only one brother with dark brown eyes. The brother with dark brown eyes and dark hair was born white headed then it turned darker as he aged. So how was my Mom able to overcome the recessive gene and pass it on to three of four boys. I love blue eyes and have passed it on to my children. Gorgeous blue eyed children and grand children. Sorry we are Gods and the rest of you plebs are mutants.%-)
Seafred, Your mom didn’t overcome anything. She passed on the recessive gene because its all she had, while your dad clearly had the recessive gene and passed it on to 3 of his 4 boys. The point of this article, though, is a common ancestor who had the mutation and is the progenitor of all peoples with blue eyes. However, if he was the only one with the gene, given our understanding of recessive genes it should have disappeared *Unless* others had the same mutation. Meaning there is not one common ancestor but many.
I have been doing some DNA testing with Family Tree DNA and in the National Genographic study. I believe we will know a lot more about this when all the latest data is in. NGeo has tested over a hundred thousand indigenous people all over the world and many like myself have put our own in the pot. I am of Viking stock and that is clear. It will take private individuals sharing data to find out what genes we share. DNA testing for ancestry is pretty new and many that take the test still don’t wish to talk about their finding in the gene department, but that will change in time. The DNA studies should put this to rest in the future with out a lot of speculation. I think??
of course we are all mutations. we all come from the a-sexual hermaphrodite to the x and y. mutation simply means change. without change, one cannot evolve. therefore, two blue-eyed blonde haired humans cannot evolve.