manderlyh Posted February 1, 2008 Share Posted February 1, 2008 Genetic mutation makes those brown eyes blue Scientists find that blue-eyed individuals have a single, common ancestor by Jeanna Bryner updated 12:01 p.m. MT, Thurs., Jan. 31, 2008People with blue eyes have a single, common ancestor, according to new research. A team of scientists has tracked down a genetic mutation that leads to blue eyes. The mutation occurred between 6,000 and 10,000 years ago, so before then, there were no blue eyes. "Originally, we all had brown eyes," said Hans Eiberg from the Department of Cellular and Molecular Medicine at the University of Copenhagen. The mutation affected the so-called OCA2 gene, which is involved in the production of melanin, the pigment that gives color to our hair, eyes and skin. "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," Eiberg said. The genetic switch is located in the gene adjacent to OCA2 and rather than completely turning off the gene, the switch limits its action, which reduces the production of melanin in the iris. In effect, the turned-down switch diluted brown eyes to blue. If the OCA2 gene had been completely shut down, our hair, eyes and skin would be melanin-less, a condition known as albinism. "It's exactly what I sort of expected to see from what we know about selection around this area," said John Hawks of the University of Wisconsin-Madison, referring to the study results regarding the OCA2 gene. Hawks was not involved in the current study. Baby blues Eiberg and his team examined DNA from mitochondria, the cells' energy-making structures, of blue-eyed individuals in countries including Jordan, Denmark and Turkey. This genetic material comes from females, so it can trace maternal lineages. They specifically looked at sequences of DNA on the OCA2 gene and the genetic mutation associated with turning down melanin production. Over the course of several generations, segments of ancestral DNA get shuffled so that individuals have varying sequences. Some of these segments, however, that haven't been reshuffled are called haplotypes. If a group of individuals shares long haplotypes, that means the sequence arose relatively recently in our human ancestors. The DNA sequence didn't have enough time to get mixed up. "What they were able to show is that the people who have blue eyes in Denmark, as far as Jordan, these people all have this same haplotype, they all have exactly the same gene changes that are all linked to this one mutation that makes eyes blue," Hawks said in a telephone interview. Melanin switch The mutation is what regulates the OCA2 switch for melanin production. And depending on the amount of melanin in the iris, a person can end up with eye color ranging from brown to green. Brown-eyed individuals have considerable individual variation in the area of their DNA that controls melanin production. But they found that blue-eyed individuals only have a small degree of variation in the amount of melanin in their eyes. "Out of 800 persons we have only found one person which didn't fit — but his eye color was blue with a single brown spot," Eiberg told LiveScience, referring to the finding that blue-eyed individuals all had the same sequence of DNA linked with melanin production. Link to comment Share on other sites More sharing options...
TRB Posted February 1, 2008 Share Posted February 1, 2008 Mutants unite! Link to comment Share on other sites More sharing options...
manderlyh Posted February 1, 2008 Author Share Posted February 1, 2008 Whatever, freaks. My sisters both have blue eyes. Link to comment Share on other sites More sharing options...
TRB Posted February 1, 2008 Share Posted February 1, 2008 So ha, we are coming to get you! Link to comment Share on other sites More sharing options...
manderlyh Posted February 1, 2008 Author Share Posted February 1, 2008 My BROWN eyes will fight the power... ...I think.... Link to comment Share on other sites More sharing options...
Sunray782 Posted February 1, 2008 Share Posted February 1, 2008 Mine will join yours and together we will defeat the mutants! Link to comment Share on other sites More sharing options...
manderlyh Posted February 1, 2008 Author Share Posted February 1, 2008 ha, TRB! Link to comment Share on other sites More sharing options...
FuzzyMerkin Posted February 1, 2008 Share Posted February 1, 2008 Mine will join yours and together we will defeat the mutants! Link to comment Share on other sites More sharing options...
TRB Posted February 1, 2008 Share Posted February 1, 2008 So you say, so you say. Don't you know blue eyes send out stronger energy beams? Superman's eyes are blue. Link to comment Share on other sites More sharing options...
FuzzyMerkin Posted February 1, 2008 Share Posted February 1, 2008 So you say, so you say. Don't you know blue eyes send out stronger energy beams? Superman's eyes are blue. And have you noted that there are only two blue-eyed smilies? :'( I think those blue-ies are trying to tell us something... Link to comment Share on other sites More sharing options...
Puck Slapping Maple Sucker Posted February 1, 2008 Share Posted February 1, 2008 ......and a beautiful mutation it is. Link to comment Share on other sites More sharing options...
alinds Posted February 1, 2008 Share Posted February 1, 2008 Well, that's hardly shocking. Link to comment Share on other sites More sharing options...
LadyRaven Posted February 1, 2008 Share Posted February 1, 2008 I'm a real big mutant then, I have green eyes. Link to comment Share on other sites More sharing options...
TheZeppyWanderer Posted February 1, 2008 Share Posted February 1, 2008 so, blue eyes are a result of evolution then, no kidding, well there's a surprise and now that we blueys (is that a word ?) have been outed as mutants, we have a genuine reason to go on the rampage, conquering the world and exploiting it's resources ......... ......... oh sorry, we've been there done that already Link to comment Share on other sites More sharing options...
Electrophile Posted February 1, 2008 Share Posted February 1, 2008 I will join the brown-eyed brigade and fight to the death to protect my planet from the pale-eyed mutants. Link to comment Share on other sites More sharing options...
Kissandra Posted February 1, 2008 Share Posted February 1, 2008 I could swear I'd heard of this years ago Link to comment Share on other sites More sharing options...
Del Zeppnile Posted February 1, 2008 Share Posted February 1, 2008 so, blue eyes are a result of evolution then, no kidding, well there's a surprise and now that we blueys (is that a word ?) have been outed as mutants, we have a genuine reason to go on the rampage, conquering the world and exploiting it's resources ......... ......... oh sorry, we've been there done that already I am a proud member of the melanin-impoverished mutant albino genetic-recessive global minority! I have a theory that since blue eyes and light skin is only a recent development in the evolution of human beings. Then it must follow that we are also an improvement over earlier models. Link to comment Share on other sites More sharing options...
Trailer Trash Posted February 1, 2008 Share Posted February 1, 2008 I have a theory that since blue eyes and light skin is only a recent development in the evolution of human beings. Then it must follow that we are also an improvement over earlier models. Or the result of in-breeding. Link to comment Share on other sites More sharing options...
FuzzyMerkin Posted February 1, 2008 Share Posted February 1, 2008 Or the result of in-breeding. Asexual reproduction, more like... Scientists find that blue-eyed individuals have a single, common ancestor Link to comment Share on other sites More sharing options...
redeyedrichard Posted February 1, 2008 Share Posted February 1, 2008 I am afraid I cannot join sides with anyone, for I am on a side of my own... ...being Red Eyed and all. Better keep these sunglasses on, wouldn't want to scare the kids. Link to comment Share on other sites More sharing options...
Bilbo the Rover Posted February 1, 2008 Share Posted February 1, 2008 My eyes are hazel, green with a smattering of brown, we have a high amount of grey eyes in my family, my daughter inherited them as well. Lot's of folks with jet black hair, pale skin and grey eyes in my clan...my sister is the oddball with brown eyes, she always felt like she was jipped ! Link to comment Share on other sites More sharing options...
MS1 Posted February 1, 2008 Share Posted February 1, 2008 My favorite physical part of a woman is the eyes, and I love blue eyes! Zooey Deschanel, for instance, has AMAZING eyes: Link to comment Share on other sites More sharing options...
59LesPaul Posted February 1, 2008 Share Posted February 1, 2008 My favorite physical part of a woman is the eyes, ................ Suuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuure........ My wife will still dispute this;but the first night I ever met her;the very first thing I noticed about her was her beautiful green eyes.-I still could look into them forever. Now;as far as the second thing I noticed,or should I say "things", I ain't sayin'..... Link to comment Share on other sites More sharing options...
Katuschka Posted February 1, 2008 Share Posted February 1, 2008 :'( This one's supposed to be crying, so it's actually just water. That's sad, isn't it. :'( That means that there is only ONE smilie with blue eyes. Link to comment Share on other sites More sharing options...
MS1 Posted February 1, 2008 Share Posted February 1, 2008 Suuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuure........ My wife will still dispute this;but the first night I ever met her;the very first thing I noticed about her was her beautiful green eyes.-I still could look into them forever. Now;as far as the second thing I noticed,or should I say "things", I ain't sayin'..... I'm not saying I don't notice other things. But eyes make my stomach flip. All the beauty of the sunset or the ocean condensed into one set of peepers- Pretty eyes can enslave me. Copious back rubs, midnight trips to the store, the whole enchilada. Link to comment Share on other sites More sharing options...
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