Scientists find that blue-eyed individuals have a single, common ancestor
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.
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.
"From this we can conclude that all blue-eyed individuals are linked to the same ancestor," Eiberg said. "They have all inherited the same switch at exactly the same spot in their DNA." Eiberg and his colleagues detailed their study in the Jan. 3 online edition of the journal Human Genetics.
That genetic switch somehow spread throughout Europe and now other parts of the world.
"The question really is, 'Why did we go from having nobody on Earth with blue eyes 10,000 years ago to having 20 or 40 percent of Europeans having blue eyes now?" Hawks said. "This gene does something good for people. It makes them have more kids." Posted by Djehuti (Member # 6698) on :
^ I have two questions...
What does the mutation for having blue eyes have to do with having more children as it's stated in the last sentence?
Also what about blue eyes in black aboriginal populations who obviously have nothing to do with the ancestors of Europeans 10,000 years ago??..
Posted by Habari (Member # 14738) on :
Is there are coloration between blue eyes and blond hair among Eurasians or Aborigenes?
Posted by HistoryFacelift (Member # 14696) on :
quote:Originally posted by Djehuti: [QB] ^ I have two questions...
What does the mutation for having blue eyes have to do with having more children as it's stated in the last sentence?
Maybe he's referring to the fact that almost half the European population have genes derived from this one person with the mutation, thus they "had more kids" I guess... ___________
My question is...since this only seems to explain blue eyes, what about green etc, light eyes in general, are these a whole different mutation all together? And if so did they mutate from the already mutated blue eyes, or from brown eyes also?
Posted by xyyman (Member # 13597) on :
If you read the passage. It says that the different light colors(non-brown) are due to the same gene. It is just different intensities/variations of how the gene plays out.
quote:Originally posted by HistoryFacelift:
quote:Originally posted by Djehuti: [QB] ^ I have two questions...
What does the mutation for having blue eyes have to do with having more children as it's stated in the last sentence?
Maybe he's referring to the fact that almost half the European population have genes derived from this one person with the mutation, thus they "had more kids" I guess... ___________
My question is...since this only seems to explain blue eyes, what about green etc, light eyes in general, are these a whole different mutation all together? And if so did they mutate from the already mutated blue eyes, or from brown eyes also?
Posted by Young H*O*R*U*S (Member # 11484) on :
quote:Originally posted by Djehuti: "The question really is, 'Why did we go from having nobody on Earth with blue eyes 10,000 years ago to having 20 or 40 percent of Europeans having blue eyes now?" Hawks said. "This gene does something good for people. It makes them have more kids."
LOL this just sounds like some sad person's wet dream. The question really is, 'Why is it that when a blue eyed person has kids with a brown eyed person, the kids ALMOST NEVER have blue eyes? but OFTEN, have brown eyes?'
Posted by Djehuti (Member # 6698) on :
^ That's an basic elementary question. Of course cross-breeding between a blue-eyed parent and brown-eyed parent produces predominantly brown-eyed children because blue-eyes is a recessive trait whereas brown eyes is dominant. Hence, why blue eyes are overall rare worldwide.
quote:Originally posted by Habari: Is there are coloration between blue eyes and blond hair among Eurasians or Aborigenes?
I don't know. The mutation for blonde hair in Aborigines is different from that of Europeans. So it may not be associated with blue eyes, since I have seen many aborigines with blue eyes and dark hair and those with dark eyes and blonde hair.
quote:Originally posted by HistoryFacelift: Maybe he's referring to the fact that almost half the European population have genes derived from this one person with the mutation, thus they "had more kids" I guess... ___________
Perhaps so.
quote:My question is...since this only seems to explain blue eyes, what about green etc, light eyes in general, are these a whole different mutation all together? And if so did they mutate from the already mutated blue eyes, or from brown eyes also?
That was my question also as there are Aboriginal groups with blue eyes who obviously have nothing to do with the ancestors of Europeans. Also there are peoples in India who are dark or even black with green eyes so obviously these result from different genetic events.
Posted by xyyman (Member # 13597) on :
for the Euro-holic
Posted by MelaninKing (Member # 17444) on :
quote:Originally posted by Djehuti: ^ I have two questions...
What does the mutation for having blue eyes have to do with having more children as it's stated in the last sentence?
Also what about blue eyes in black aboriginal populations who obviously have nothing to do with the ancestors of Europeans 10,000 years ago??..
That is an INACCURACY. Blue eyes indicate OCA syndrome, whcih also indicates melanin deficiency. Another symptom of OCA is LOW REPRODUCTION rates. This can be verified within the CDC birthrate by race statistics which show whites and jews as having the lowest birth rates of all of the world's groups.
As I recall, birth rate by race looks something like this;
Births per 10000
Black - 200/10000 Hispanic -220/10000 Asian - 180/10000 White - 90/10000 Jews aren't classified as race, but their birth rate is the lowest due to a very high infant mortality rate as a DIRECT result of DNA and reproductive damage. http://www.jewishvirtuallibrary.org/jsource/Health/genetics.html
Jews - 80/10000
I also notice the article avoids actually stating SPECIFICALLY what OCA is, as in ALBINISM, since it would valididate that ALL blue eyed people are OCA carriers.
Posted by Djehuti (Member # 6698) on :
^ If what you say is so, then how do you explain blue eyes in NON-albino populations?? Sure blue eyes are extremely rare among black Africans except albinos, but they still occur. The topic article I posted dealt with Eurasians, specifically Europeans with blue eyes so your point is null.
Posted by MelaninKing (Member # 17444) on :
^ I believe your question is prompted by a misunderstanding of the term, Albinism. Albinos are not all milky white. Many appear to look like "normal" whites with a little tan, or may even be dark skinned like the blue eyed black women shown above. As I stated earlier, a key indicator of OCA is any eye color other than BROWN. Hence, the OCULAR in OCA. Likewise, some brown eyed individuals may also carry OCA. Those having blue, green, hazel or any color than dark brown will be susceptible to poor eyesight (less than optimum), and eye disease. Over time and exposure, radiation from sunlight will cause further damage since melanin density is meant to protect from this very thing.
Looks like someone has bumped Marc's thread that contains more details of OCA classification.
Posted by Mike111 (Member # 9361) on :
Albinism
Albinism is a form of hypopigmentary congenital disorder, characterized by a partial or total lack of melanin pigment in the eyes, skin and hair.
Albinism is hereditary; The principal gene which results in albinism prevents the body from making the usual amounts of the pigment melanin. Most forms of albinism are the result of the biological inheritance of genetically recessive alleles (genes) passed from both parents of an individual, though some rare forms are inherited from only one parent.
The gene OCA2, when in a variant form, the gene causes the pink eye color and hypopigmentation common in human albinism. Different SNPs within OCA2 are strongly associated with blue and green eyes.
Hair color is the pigmentation of hair follicles due to two types of melanin, eumelanin and pheomelanin. Generally, if more melanin is present, the color of the hair is darker; if less melanin is present, the hair is lighter. Blond hair can have almost any proportion of phaeomelanin and eumelanin, but both only in small amounts.
The human eye is quite large and thus produces enough pigment to lend opacity to the eye, often colouring the iris pale blue. However, there are cases in which the eyes of an albinistic person appear red or purple, depending on the amount of pigment present. Lack of pigment in the eyes also results in problems with vision, related and unrelated to photosensitivity.
Ya gotta give White people credit; they are the only ones who would try to make a state of ILL HEALTH and DISEASE, into something others should envy.
But then again, what does that make the ass-holes who believe them? Posted by The Explorer (Member # 14778) on :
The study referenced in the intro article can be dangerous when it gets into the wrong hands. Some confused individuals have taken it so far to imply that each and everywhere 'blue eyes' occurs, it must be traced back to some unknown obscure "caucasian". Even sparse and random occurrences in sub-Saharan Africa is explained off as the contribution of this supposed 'caucasian' ancestor, without material support.
The study simply studied a couple of *families* in two European countries where 'blue eyes' is not uncommon, and a few individuals from Jordan.
So, of course, some degree of linkage disequilibrium is to be expected here, when you study people from the same family, and in a country where 'blue eyes' is fairly common.
No sub-Saharan African groups were analyzed here, let alone from the greater part of Asia and elsewhere.
Posted by Recovering Afro-holic (Member # 17311) on :
Oh man! this is fvcking entertaining to see Afro-loons going to great lengths to try to twist what is pretty much an unambiguous statement:
"People with blue eyes have a single, common ancestor, according to new research."
RFLOL! You guys are really awesome. You will fight tooth and nail to defend that pseudo-paradigm of yours. Science says (X) but if Afrocentrism says (Y) then you can bet your bottom dollar some fool like Explorer will reject it. Afrocentrists are ideologues, not scientists or academics. It is as simple as that.
quote:Originally posted by The Explorer: The study referenced in the intro article can be dangerous when it gets into the wrong hands. Some confused individuals have taken it so far to imply that each and everywhere 'blue eyes' occurs, it must be traced back to some unknown obscure "caucasian".
Posted by The Explorer (Member # 14778) on :
Dumb ku klux klan puppet,
Where can I find a study of multiple *unrelated* sub-Saharan Africans, and just not some study of two European family members, along with a large size global sample, that says the blue eyes occurrence just about anywhere, is the contribution of some fictitious "caucasian"?
Posted by osirion (Member # 7644) on :
quote:Originally posted by The Explorer: The study referenced in the intro article can be dangerous when it gets into the wrong hands. Some confused individuals have taken it so far to imply that each and everywhere 'blue eyes' occurs, it must be traced back to some unknown obscure "caucasian". Even sparse and random occurrences in sub-Saharan Africa is explained off as the contribution of this supposed 'caucasian' ancestor, without material support.
The study simply studied a couple of *families* in two European countries where 'blue eyes' is not uncommon, and a few individuals from Jordan.
So, of course, some degree of linkage disequilibrium is to be expected here, when you study people from the same family, and in a country where 'blue eyes' is fairly common.
No sub-Saharan African groups were analyzed here, let alone from the greater part of Asia and elsewhere.
I might agree with you but you haven't provided any scientific evidence to support your position.
What reports shows that this mutation is found in people that are not related to Caucasians (no matter how distant)?
Posted by The Explorer (Member # 14778) on :
quote:Originally posted by osirion:
I might agree with you but you haven't provided any scientific evidence to support your position.
What reports shows that this mutation is found in people that are not related to Caucasians (no matter how distant)?
Moron, it don't give a hoot about your agreement or lack there of. The burden is on you to show that the random occurrence of 'blue eyes' in sub-Saharan Africans is the handy work of some imaginary 'crakasian'. The burden is on you, not I.
Posted by Recovering Afro-holic (Member # 17311) on :
You are asking me where?! (LOL) Ohhhh so I get it! You are like an engineer who puts the cartwheel before the horse. You refuted the study not based on some existing research you had come across. Oh no no no, not at all. It is based on some hypothetical research that you will one day come across. A research no doubt that will counter the study. Hold on a second, I'm bout to lose my composure here..... LOL!!!!!
The quote function is awesome! I gots ya in quotes buddy! I want the entire readership to see Afrocentrists for what and who they truly are. Keep it up Explorer. Keep it up sir.
quote:Originally posted by The Explorer: Dumb ku klux klan puppet,
Where can I find a study of multiple *unrelated* sub-Saharan Africans, and just not some study of two European family members, along with a large size global sample, that says the blue eyes occurrence just about anywhere, is the contribution of some fictitious "caucasian"?
Posted by The Explorer (Member # 14778) on :
quote:Originally posted by Recovering Afro-holic:
You are asking me where?!
Yes, klutz. You are that dummy who posted a study without understanding a damn thing about it.
quote: (LOL) Ohhhh so I get it! You are like an engineer who puts the cartwheel before the horse. You refuted the study not based on some existing research you had come across.
Absolutely, I *refuted* your amateurish-use of the study. You disagree with the refutation; bring on the counter-evidence.
Posted by Recovering Afro-holic (Member # 17311) on :
quote:Originally posted by The Explorer: Yes, klutz. You are that dummy who posted a study without understanding a damn thing about it.
You have got to be a joke. The study stands on its own, turd.
quote:Absolutely, I *refuted* your amateurish-use of the study. You disagree with the refutation; bring on the counter-evidence.
You are a joke. You refute a study with an assinine opinion and you think I have to counter an opinion with a study?! (LOL) Wrong dude. I provided a study. You challenged it so the onus is on your porch monkey ass to come up w/research that debunks the study I provided.
You guys are pathetic but entertaining (LOL).
Posted by The Explorer (Member # 14778) on :
quote:Originally posted by Recovering Afro-holic:
You have got to be a joke. The study stands on its own, turd.
armpit of fucking redneck. How does the study stand on its own, when you are using it to make some unfounded far-reaching bizarre claim that random occurrences of 'blue eyes' in sub-Saharan Africans is secondary to 'crakasian' gene flow? Demonstrate, donkey's smelly ass.
quote: You are a joke. You refute a study with an assinine opinion and you think I have to counter an opinion with study?
You are a bucket of shyt. If my points were "assinine opinion", you'd be ready with counter-evidence, not bitching like a little tinnie school girl whose lunch-box got taken away.
quote: ! (LOL) Wrong dude. I provided a study. You challenged it so the onus is on your porch monkey ass to come up w/research that debunks the study I provided.
filfthy crakasian dyke. Bring on the counter-evidence. Your pussy-talk ain't cutting it.
Posted by osirion (Member # 7644) on :
quote:Originally posted by The Explorer:
quote:Originally posted by osirion:
I might agree with you but you haven't provided any scientific evidence to support your position.
What reports shows that this mutation is found in people that are not related to Caucasians (no matter how distant)?
Moron, it don't give a hoot about your agreement or lack there of. The burden is on you to show that the random occurrence of 'blue eyes' in sub-Saharan Africans is the handy work of some imaginary 'crakasian'. The burden is on you, not I.
Always so explosive. There are 4 separate scientific reports that link this particular gene mutation to Caucasians - as in people of the Caucasus area.
Burden is now on you since you disagree with the findings.
Is this a matter of religion or science? Faith or scientific method?
When I am religious its usually about religious issues not scientific ones.
Posted by The Explorer (Member # 14778) on :
quote:Originally posted by osirion:
Always so explosive. There are 4 separate scientific reports that link this particular gene mutation to Caucasians - as in people of the Caucasus area.
And I care, why?
quote:
Burden is now on you since you disagree with the findings.
With what findings. Tell me, findings from:
1)Large samples of *unrelated* 'blue-eyed' individuals, in both locales where 'blue-eye' is common and not common -- large enough samples from world over, not just from say, a few families in Denmark, *5* individuals from Turkey, and *2* from Jordan.
2)Large enough samples of sub-Saharan Africans with 'blue-eyes' that are *unrelated*
Tell me about the findings of the specific markers associated with 'blue-eye' in all of these regions.
Yeah, looking at all this, the burden is still on me...NOT, fool. Drop the cowardly evasive shenanigans and come up with the answers, quick.
Posted by xyyman (Member # 13597) on :
Don't want to speak for the brotha but how is blue eye explained for black Africans with seemingly no European admixture. I thought it is a double recessive gene. (sorry Mike and Mininarmer I am not into whites are alibinos theory). How can two black Africans make a blue eye baby.
I have personally seen one kid(Black) without seemingly European influence with the deepest blue eye. I am sure there are many like that.
Did the study take into account this phenomenon.
Maybe it is like white skin. . . Asians and Europeans both developed it.
Bottom line. Looks like the Euros are talking about themselves not realizing Black people also have blue eyes without European admixture.
The study is incomplete.
Posted by Apocalypse (Member # 8587) on :
The body of the study posted at the top says this:
quote:Out of 800 persons we have only found one person which didn't fit
Well that 1 person is all you need to refute the notion that all blue-eyed people are necessarily related.
Posted by xyyman (Member # 13597) on :
Then MOST white people are related. . . inbreeding. . .lack of diversity. Then there is another source of blue eyes. Maybe all blue eye Europeans are related.
Posted by Jari-Ankhamun (Member # 14451) on :
we are all related, though I doubt all "whites" are related. Also not all blue eyed Euros are related...some have black hair or blond hair or red with blue eyes and there r differnt shades of blue
![[Big Grin]](biggrin.gif)
this just sounds like some sad person's wet dream. The question really is, 'Why is it that when a blue eyed person has kids with a brown eyed person, the kids ALMOST NEVER have blue eyes? but OFTEN, have brown eyes?'
![[Embarrassed]](redface.gif)
That's an basic elementary question. Of course cross-breeding between a blue-eyed parent and brown-eyed parent produces predominantly brown-eyed children because blue-eyes is a recessive trait whereas brown eyes is dominant. Hence, why blue eyes are overall rare worldwide.