Posted on 02/02/2008 1:02:18 PM PST by G8 Diplomat
People 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.
(Excerpt) Read more at msnbc.msn.com ...
Yes. On second reading, the first comment came out a bit harsher than intended. That was an actual question; as the second comment suggests, figured that a mutation causing blue eyes a few millennia ago was old, commonly-accepted news.
I retina papers that this finding has been disputed by others.
Not a bad headline. Let’s call it the Crystal Gayle gene.
“Lighter eyes let in more light, and are more sensitive to sunlight.”
This blog entry from the Gene Expression website talks about this and theorizes that this different amount of light changes the actual personality of blue-eyed people.
http://www.gnxp.com/blog/2007/11/blue-eyed-ice-queens-and-brown-eyed.php
It also claims more men are blue-eyed and more women are green eyed. Also, the less emotional and more analytical blue-eyed men are more often found in professions that correspond with those traits such as engineers. There’s an exception for East Asians with a plausible reason given. It’s a very interesting theory (and I’d never heard of anything like it before) but more recent studies need to be done.
Wow, that’s interesting. Blue eyes only showed up among the Europeans—Russians included (and as they colonized places, subsequently in Americans, Canadians, and Australians/NZ) I guess because the sun was less intense there than in Africa, Asia, and the Middle East. But I had no idea the eye color had an affect on behavior. Cool stuff.
There's the promotion of genetics as the primary influencer of personality. The use of the term 'race-baiting' as an attempt to brush aside criticism that conclusions are not only racist, but not based solidly on facts. And then there's the particularly revealing quote: "If they would have been black [they] probably would have gotten flak", which the author chose to bold. Add on the traditional tendency of 'startling' *evidence* that 'whites' are more intelligent, compassionate/friendly, beautiful than all the other races (with the exception that some suggest East Asians are more intelligent than 'whites,' but also more cowardly and less friendly/compassionate). Just how full of themselves can some people be?
The people who make such arguments are probably: ugly; moderate intelligence; and--obviously--are lacking in the kindness department.
You can find a 'white' who is more intelligent than a 'black.' You can find a 'black' who is more intelligent than a 'white.'
You can find a 'brown' who is more compassionate than a 'yellow.' You can find a 'yellow' who is more compassionate than a 'brown.'
As for beauty, will state that there's a toss-up. As some here suggest, colorful traits such as blue eyes, blondism (includes red-hair) do give 'whites' a leg up. However, in terms of structure, as a percentage, the most beautiful people seem to be in an area surrounding Mesopotamia. That is, if you were to pick the most beautiful genetic nation, that nation would be around Mesopotamia. However, if you were to pick the top 100 most beautiful people in the world, Europeans would be overwhelmingly represented. And yet, beauty is finicky, and not for PC reasons. Only a few generations ago, extremely pale-skinned men were considered more attractive than more tanned ones--that has since changed. A few generations before, an attractive woman would be what is now considered fat. During the Middle Ages, a high, broad forehead was attractive. That has become less of a decisive trait. And that's just taking a glimpse at Western standards of beauty. That standard has so dominated the global view on beauty that finding out what the local standards were before the Age of Colonialism. In contrast to the egotism of some 'white' racists, 'whites' might not have been universally considered beautiful upon first contact. If some surviving text about non-Europeans' views on European appearance is discovered, that could be revealing, either way.
In any case, prideful people--especially those who have no reason to be proud--are akin to a full-body mosquito bite.
/rant.
I guess we're not supposed to be curious about how the great variety of physical differences between humans came about and just leave it be, but people are going to always wonder about it and seek answers, especially as the studies on genetics advance. I certainly don't want to add any hurt to anyone in anyway so I'll apologize if I did offend.
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