Potential Origins of Europeans Found
By RANDOLPH E. SCHMID
AP Science Writer
WASHINGTON (AP) -- A study of DNA from ancient farmers in Europe shows sharp differences from that of modern Europeans—results that are likely to add fuel to the debate over European origins.
Researchers led by Wolfgang Haak of Johannes Gutenberg University in Mainz, Germany, argue that their finding supports the belief that modern residents of central Europe descended from Stone Age hunter-gatherers who were present 40,000 years ago, and not the early farmers who arrived thousands of years later.
But other anthropologists questioned that conclusion, arguing that the available information isn't sufficient to support it.
Haak's team used DNA from 24 skeletons of farmers from about 7,500 years ago, collected in Germany, Austria and Hungary. Six of the skeletons—25 percent—belonged to the ``N1a'' human lineage, according to genetic signatures in their mitochondrial DNA, which is inherited from the mother.
The N1a marker is extremely rare in modern Europeans, appearing in just 0.2 percent.
``This was a surprise. I expected the distribution of mitochondrial DNA in these early farmers to be more similar to the distribution we have today in Europe,'' co-author Joachim Burger, also from Johannes Gutenberg University, said in a statement.
``Our paper suggests that there is a good possibility that the contribution of early farmers could be close to zero,'' added co-author Peter Forster from the University of Cambridge in England.
Absence of the marker in modern people indicates they are descended from ancient hunter-gatherers rather than the later-arriving farmers, the researchers said.
But others challenged that conclusion.
``The data are new, the analysis is not compelling, and the conclusions are illogical,'' said anthropologist Milford H. Wolpoff of the University of Michigan.
Anthropologist Joao Zilhao of the University of Bristol, England, noted that the study didn't compare the DNA of the ancient farmers with that of the ancient hunter-gatherers, adding that there are plenty of hunter-gatherer burials in German cave sites that could have been sampled for comparison.
Without that comparison it's hard to say that the difference between modern DNA and that of the ancient farmers means current people are descended from the ancient hunter-gatherers.
``In this particular case, the reason may be because of a farmer input that was subsequently diluted, assuming that the N1a haplotype is a marker of spreading farmers, and that it was as rare in pre-Neolithic Europe as it is today,'' Zilhao said.
But, he added, ``I see nothing in the data that would necessarily carry the exclusion of, for instance, the opposite hypothesis ... that (the N1a marker) represents the incorporation of hunter-gatherer females in the farming communities that are coming into Europe about 7,500 years ago, that incorporation being in such small numbers that, eventually, it all but disappeared.''
The research was funded by the German Federal Ministry for Education and Research.
Potential Origins of Europeans Found
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Scientists Find A DNA Change That Accounts For White Skin
Scientists Find A DNA Change That Accounts For White Skin
By Rick WeissWashington Post Staff Writer
Friday, December 16, 2005; Page A01
Scientists said yesterday that they have discovered a tiny genetic mutation that largely explains the first appearance of white skin in humans tens of thousands of years ago, a finding that helps solve one of biology's most enduring mysteries and illuminates one of humanity's greatest sources of strife.
The work suggests that the skin-whitening mutation occurred by chance in a single individual after the first human exodus from Africa, when all people were brown-skinned. That person's offspring apparently thrived as humans moved northward into what is now Europe, helping to give rise to the lightest of the world's races.
Researchers and regulators are reshaping the landscape of science, medicine and health, engendering hope -- and disquiet -- for the future of humanity.
Leaders of the study, at Penn State University, warned against interpreting the finding as a discovery of "the race gene." Race is a vaguely defined biological, social and political concept, they noted, and skin color is only part of what race is -- and is not.
In fact, several scientists said, the new work shows just how small a biological difference is reflected by skin color. The newly found mutation involves a change of just one letter of DNA code out of the 3.1 billion letters in the human genome -- the complete instructions for making a human being.
"It's a major finding in a very sensitive area," said Stephen Oppenheimer, an expert in anthropological genetics at Oxford University, who was not involved in the work. "Almost all the differences used to differentiate populations from around the world really are skin deep."
The work raises a raft of new questions -- not least of which is why white skin caught on so thoroughly in northern climes once it arose. Some scientists suggest that lighter skin offered a strong survival advantage for people who migrated out of Africa by boosting their levels of bone-strengthening vitamin D; others have posited that its novelty and showiness simply made it more attractive to those seeking mates.
The work also reveals for the first time that Asians owe their relatively light skin to different mutations. That means that light skin arose independently at least twice in human evolution, in each case affecting populations with the facial and other traits that today are commonly regarded as the hallmarks of Caucasian and Asian races.
Several sociologists and others said they feared that such revelations might wrongly overshadow the prevailing finding of genetics over the past 10 years: that the number of DNA differences between races is tiny compared with the range of genetic diversity found within any single racial group. Even study leader Keith Cheng said he was at first uncomfortable talking about the new work, fearing that the finding of such a clear genetic difference between people of African and European ancestries might reawaken discredited assertions of other purported inborn differences between races -- the most long-standing and inflammatory of those being intelligence.
"I think human beings are extremely insecure and look to visual cues of sameness to feel better, and people will do bad things to people who look different," Cheng said.
The discovery, described in today's issue of the journal Science, was an unexpected outgrowth of studies Cheng and his colleagues were conducting on inch-long zebra fish, which are popular research tools for geneticists and developmental biologists. Having identified a gene that, when mutated, interferes with its ability to make its characteristic black stripes, the team scanned human DNA databases to see if a similar gene resides in people.
To their surprise, they found virtually identical pigment-building genes in humans, chickens, dogs, cows and many others species, an indication of its biological value. They got a bigger surprise when they looked in a new database comparing the genomes of four of the world's major racial groups. That showed that whites with northern and western European ancestry have a mutated version of the gene.
Skin color is a reflection of the amount and distribution of the pigment melanin, which in humans protects against damaging ultraviolet rays but in other species is also used for camouflage or other purposes. The mutation that deprives zebra fish of their stripes blocks the creation of a protein whose job is to move charged atoms across cell membranes, an obscure process that is crucial to the accumulation of melanin inside cells.
Researchers and regulators are reshaping the landscape of science, medicine and health, engendering hope -- and disquiet -- for the future of humanity.
Humans of European descent, Cheng's team found, bear a slightly different mutation that hobbles the same protein with similar effect. The defect does not affect melanin deposition in other parts of the body, including the hair and eyes, whose tints are under the control of other genes.
A few genes have previously been associated with human pigment disorders -- most notably those that, when mutated, lead to albinism, an extreme form of pigment loss. But the newly found glitch is the first found to play a role in the formation of "normal" white skin. The Penn State team calculates that the gene, known as slc24a5, is responsible for about one-third of the pigment loss that made black skin white. A few other as-yet-unidentified mutated genes apparently account for the rest.
Although precise dating is impossible, several scientists speculated on the basis of its spread and variation that the mutation arose between 20,000 and 50,000 years ago. That would be consistent with research showing that a wave of ancestral humans migrated northward and eastward out of Africa about 50,000 years ago.
Unlike most mutations, this one quickly overwhelmed its ancestral version, at least in Europe, suggesting it had a real benefit. Many scientists suspect that benefit has to do with vitamin D, made in the body with the help of sunlight and critical to proper bone development.
Sun intensity is great enough in equatorial regions that the vitamin can still be made in dark-skinned people despite the ultraviolet shielding effects of melanin. In the north, where sunlight is less intense and cold weather demands that more clothing be worn, melanin's ultraviolet shielding became a liability, the thinking goes.
Today that solar requirement is largely irrelevant because many foods are supplemented with vitamin D.
Some scientists said they suspect that white skin's rapid rise to genetic dominance may also be the product of "sexual selection," a phenomenon of evolutionary biology in which almost any new and showy trait in a healthy individual can become highly prized by those seeking mates, perhaps because it provides evidence of genetic innovativeness.
Cheng and co-worker Victor A. Canfield said their discovery could have practical spinoffs. A gene so crucial to the buildup of melanin in the skin might be a good target for new drugs against melanoma, for example, a cancer of melanin cells in which slc24a5 works overtime.
But they and others agreed that, for better or worse, the finding's most immediate impact may be an escalating debate about the meaning of race.
Recent revelations that all people are more than 99.9 percent genetically identical has proved that race has almost no biological validity. Yet geneticists' claims that race is a phony construct have not rung true to many nonscientists -- and understandably so, said Vivian Ota Wang of the National Human Genome Research Institute in Bethesda.
"You may tell people that race isn't real and doesn't matter, but they can't catch a cab," Ota Wang said. "So unless we take that into account it makes us sound crazy."
By Rick WeissWashington Post Staff Writer
Friday, December 16, 2005; Page A01
Scientists said yesterday that they have discovered a tiny genetic mutation that largely explains the first appearance of white skin in humans tens of thousands of years ago, a finding that helps solve one of biology's most enduring mysteries and illuminates one of humanity's greatest sources of strife.
The work suggests that the skin-whitening mutation occurred by chance in a single individual after the first human exodus from Africa, when all people were brown-skinned. That person's offspring apparently thrived as humans moved northward into what is now Europe, helping to give rise to the lightest of the world's races.
Researchers and regulators are reshaping the landscape of science, medicine and health, engendering hope -- and disquiet -- for the future of humanity.
Leaders of the study, at Penn State University, warned against interpreting the finding as a discovery of "the race gene." Race is a vaguely defined biological, social and political concept, they noted, and skin color is only part of what race is -- and is not.
In fact, several scientists said, the new work shows just how small a biological difference is reflected by skin color. The newly found mutation involves a change of just one letter of DNA code out of the 3.1 billion letters in the human genome -- the complete instructions for making a human being.
"It's a major finding in a very sensitive area," said Stephen Oppenheimer, an expert in anthropological genetics at Oxford University, who was not involved in the work. "Almost all the differences used to differentiate populations from around the world really are skin deep."
The work raises a raft of new questions -- not least of which is why white skin caught on so thoroughly in northern climes once it arose. Some scientists suggest that lighter skin offered a strong survival advantage for people who migrated out of Africa by boosting their levels of bone-strengthening vitamin D; others have posited that its novelty and showiness simply made it more attractive to those seeking mates.
The work also reveals for the first time that Asians owe their relatively light skin to different mutations. That means that light skin arose independently at least twice in human evolution, in each case affecting populations with the facial and other traits that today are commonly regarded as the hallmarks of Caucasian and Asian races.
Several sociologists and others said they feared that such revelations might wrongly overshadow the prevailing finding of genetics over the past 10 years: that the number of DNA differences between races is tiny compared with the range of genetic diversity found within any single racial group. Even study leader Keith Cheng said he was at first uncomfortable talking about the new work, fearing that the finding of such a clear genetic difference between people of African and European ancestries might reawaken discredited assertions of other purported inborn differences between races -- the most long-standing and inflammatory of those being intelligence.
"I think human beings are extremely insecure and look to visual cues of sameness to feel better, and people will do bad things to people who look different," Cheng said.
The discovery, described in today's issue of the journal Science, was an unexpected outgrowth of studies Cheng and his colleagues were conducting on inch-long zebra fish, which are popular research tools for geneticists and developmental biologists. Having identified a gene that, when mutated, interferes with its ability to make its characteristic black stripes, the team scanned human DNA databases to see if a similar gene resides in people.
To their surprise, they found virtually identical pigment-building genes in humans, chickens, dogs, cows and many others species, an indication of its biological value. They got a bigger surprise when they looked in a new database comparing the genomes of four of the world's major racial groups. That showed that whites with northern and western European ancestry have a mutated version of the gene.
Skin color is a reflection of the amount and distribution of the pigment melanin, which in humans protects against damaging ultraviolet rays but in other species is also used for camouflage or other purposes. The mutation that deprives zebra fish of their stripes blocks the creation of a protein whose job is to move charged atoms across cell membranes, an obscure process that is crucial to the accumulation of melanin inside cells.
Researchers and regulators are reshaping the landscape of science, medicine and health, engendering hope -- and disquiet -- for the future of humanity.
Humans of European descent, Cheng's team found, bear a slightly different mutation that hobbles the same protein with similar effect. The defect does not affect melanin deposition in other parts of the body, including the hair and eyes, whose tints are under the control of other genes.
A few genes have previously been associated with human pigment disorders -- most notably those that, when mutated, lead to albinism, an extreme form of pigment loss. But the newly found glitch is the first found to play a role in the formation of "normal" white skin. The Penn State team calculates that the gene, known as slc24a5, is responsible for about one-third of the pigment loss that made black skin white. A few other as-yet-unidentified mutated genes apparently account for the rest.
Although precise dating is impossible, several scientists speculated on the basis of its spread and variation that the mutation arose between 20,000 and 50,000 years ago. That would be consistent with research showing that a wave of ancestral humans migrated northward and eastward out of Africa about 50,000 years ago.
Unlike most mutations, this one quickly overwhelmed its ancestral version, at least in Europe, suggesting it had a real benefit. Many scientists suspect that benefit has to do with vitamin D, made in the body with the help of sunlight and critical to proper bone development.
Sun intensity is great enough in equatorial regions that the vitamin can still be made in dark-skinned people despite the ultraviolet shielding effects of melanin. In the north, where sunlight is less intense and cold weather demands that more clothing be worn, melanin's ultraviolet shielding became a liability, the thinking goes.
Today that solar requirement is largely irrelevant because many foods are supplemented with vitamin D.
Some scientists said they suspect that white skin's rapid rise to genetic dominance may also be the product of "sexual selection," a phenomenon of evolutionary biology in which almost any new and showy trait in a healthy individual can become highly prized by those seeking mates, perhaps because it provides evidence of genetic innovativeness.
Cheng and co-worker Victor A. Canfield said their discovery could have practical spinoffs. A gene so crucial to the buildup of melanin in the skin might be a good target for new drugs against melanoma, for example, a cancer of melanin cells in which slc24a5 works overtime.
But they and others agreed that, for better or worse, the finding's most immediate impact may be an escalating debate about the meaning of race.
Recent revelations that all people are more than 99.9 percent genetically identical has proved that race has almost no biological validity. Yet geneticists' claims that race is a phony construct have not rung true to many nonscientists -- and understandably so, said Vivian Ota Wang of the National Human Genome Research Institute in Bethesda.
"You may tell people that race isn't real and doesn't matter, but they can't catch a cab," Ota Wang said. "So unless we take that into account it makes us sound crazy."
A WHITE MUTATE .....THAT ORIGINATED FROM AFRICA ....WHOAAA . THATS DEFINATELY THE TRUTH.
NOTHING NEW HERE !!.......
MAYBE A SUNTAN AND MIXING WITH BLACK GENETICS CAN HELP STOP THE MAJORITY OF SKIN CANCER AND SPOTTED SKIN , LIVER SPOTS , GROWTHS AND EARLY AGING IN WHITES WHEN THEY TURN 30.
MELANIN REIGNS SUPREME.
NOTHING NEW HERE !!.......
MAYBE A SUNTAN AND MIXING WITH BLACK GENETICS CAN HELP STOP THE MAJORITY OF SKIN CANCER AND SPOTTED SKIN , LIVER SPOTS , GROWTHS AND EARLY AGING IN WHITES WHEN THEY TURN 30.
MELANIN REIGNS SUPREME.
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johnnny
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-i believe that the africans that moved to europe to live ,over time lost the melanin in there skin because the amounts of melanin in there skin was blocking there absorbtion of the vitamin B12, thats only one genetic code gene
-because i think its above 42 degrees latitude that the sun isnt as bright
-in the article it says biologically there is no such thing as race, but we are all humans
-Vitamin B12 can be found in all fruits and veggies now
-personally i hate those dam farmer tans
-because i think its above 42 degrees latitude that the sun isnt as bright
-in the article it says biologically there is no such thing as race, but we are all humans
-Vitamin B12 can be found in all fruits and veggies now
-personally i hate those dam farmer tans
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johnnny
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- Joined: September 13th, 2006, 5:05 pm
- Location: Ontario, Canada
-Nickels you dont have to be black to not get sun burned, i was lucky enough to be born with skin that doesnt burn or turn red when im in the sun for extended periodsNICKELS wrote:A WHITE MUTATE .....THAT ORIGINATED FROM AFRICA ....WHOAAA . THATS DEFINATELY THE TRUTH.
NOTHING NEW HERE !!.......
MAYBE A SUNTAN AND MIXING WITH BLACK GENETICS CAN HELP STOP THE MAJORITY OF SKIN CANCER AND SPOTTED SKIN , LIVER SPOTS , GROWTHS AND EARLY AGING IN WHITES WHEN THEY TURN 30.
MELANIN REIGNS SUPREME.
-when im out with my friends im usually always 99.9% of the time the only one not burning, ive passed out drunk in the sun once with my back to the sun and all that happened was that my skin turned a deep bronze brown
-our ozone layer is depleting and i bet you in about 50 years it wont matter what colour your skin is were all going to get burned
-The Sun dont care
DOn't know... The term "Asian" is so vague.
I mean, as far as I'm concerned, the number of Thai's, Cambodians, South Vietnamese, and Filipino's/Malaysians/Indonesians tend to be tan yellow to dark brownish as far as i can recall.
I guess when they mentioned Asians, they were strictly talking about Koreans or something lol.
I mean, as far as I'm concerned, the number of Thai's, Cambodians, South Vietnamese, and Filipino's/Malaysians/Indonesians tend to be tan yellow to dark brownish as far as i can recall.
I guess when they mentioned Asians, they were strictly talking about Koreans or something lol.
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Old Shatterhand
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Francis Collins, the director of the human genome project has asserted that humans derive from an original sampling of humans from an original location (and he would be in a position to know the aggregate of modern science's current [though still somewhat imperfect] results on the origins of humanity).A Ghost wrote:I already knew humans are derived from Africa.
The oldest human ever found was found in Africa, they named her "Lucy"
The location of humanity's origin indicated by the mDNA and yDNA analysis is eastern Africa, not the traditional biblical site, Mesopotamia. Identification of the eastern African site, however, is based on the observations that east Africans manifest the greatest genetic diversity of all humanity's ethnic groups-- and on the assumption that human migration and human mating is random.
The latter assumption fails the test; however, of both history and observation. Human migration and human mating practices are far more random. For example, archeological evidence testify to the early, rapid migration of humanity from a single location to diverse distant lands, whereupon the migrating peoples ceased their migration and settled in their chosen destinations (1).
In most human population groups, people willingly consider a diversity of ethnicities for marriage partners. But, especially in Africa, this was not always the case. For example, 19th-century European explorers to central Africa were surprised to observe tribes of pygmies living adjacent to tribes of extraordinarily tall people.
Given that not all human groups migrate and mate like other species, the genetic evidence for human origins simply identifies the single location for the origin of humanity as somewhere near northeastern Africa, which could include any region near the junction of Asia, Europe, and Africa.
The genetic evidence for the location of humanity's origin remains somewhat ambiguous (in scientific terms).
The oldest member of Australopithecus, A. anamensis, existed between
4.2 and 3.8 million years ago, based on fossils recovered near Lake Turkana Kenya. Australopithecus afarensis fossils have been recovered in eastern Africa and date to between 4 and 3 million years old. "Lucy" (discovered in the early 1970s by Donald Johnson) is one of the best-known specimens.
While there is no DNA analysis for Lucy, mDNA analysis exists for a more modern group of hominids known as Neanderthal. What's important about this analysis is that it does not, in any way, overlap mDNA for humans (earliest mDNA on hand dates as far back as 25,000 years ago). This observation coupled with marked differences between Neanderthal and human mDNA establish beyond reasonable doubt that Neanderthals made no contribution to the human gene pool.
Another interesting group H. erectus manifests morphological features radically different from either humans or Neanderthals and because all three species experience no observable evolutionary change, it appears highly unlikely that H. erectus could be the ancestor of either Neaderthals, archaic H. Sapiens, or modern humans.
Wherever extensive fossil evidence exists, it shows that individuals within the different hominid species mature at a much faster rate than do humans. For example, the skull of a H. erectus infant (about one year old at the time of death) revealed a brain size about 84 percent of that of an adult. This size compares with 50 percent for a one year old human and about 80 percent for a one year old modern ape. Likewise comparisons of Neanderthal skulls from individuals ranging in age at the time of death from six months to young adulthood show both a much more rapid craniofacial maturation and a much more rapid dental development than humans manifest.
Long lasting childhood and adolescence during with the brain continues to grow and develop appears to be a unique hallmark of the human species. Humans beings are vastly over-endowed for a hunter-gatherer or simple agricultural lifestyle. Though many examples are cited, dexterity, intellectual capacity, and sex drive are amongh those that set Homo sapiens sapiens apart from all other hominids and animals.
Calculations based on new findings place the date for the first mDNA woman close to 50,000 years ago in line with the yDNA date and corresponds with the biblical date for the creation of Adam and Eve basedon reasonable calibration of the Gensis genealogies. The dates for the explosive emergence of advanced art, advanced tools, complex language, clothing, and jewelry corrobate this timeing for the first human pair. This distinctive provides another support to a huge volume of support for the conclusion that hominids did not give rise to human beings.
There is much much more to discuss along these lines. Much much more. But I have to get back to living this gift we call life
. Peace and God bless you.-------------------
(1)Vincent Macaulay et al., "Single Rapid Costal Settlement of Asia Revealed by Analysis of Complete Mitochondrial Genomes," Science 308 (2005): 1034-1036.
all man origin is from africa , the only way that will change is if a white scentist feeds the world his info , of a new origin somewhere else.....to keep the history of the first humans out of africa and to discredit the skeletal bones and intellgence of the species........everything is suspect in this world when its controlled by the majority of one race.
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Mcminister
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