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Biotech Science

DNA Suggests Three Basic Human Groups 459

Death Metal writes "All of Earth's people, according to a new analysis of the genomes of 53 populations, fall into just three genetic groups. They are the products of the first and most important journey our species made — the walk out of Africa about 70,000 years ago by a small fraction of ancestral Homo sapiens."
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DNA Suggests Three Basic Human Groups

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  • As far as I can tell, this story attempts to make three points:

    1. Human genomes tend to cluster into three groups: african, eurasian, and east asian.

    2. We expected that the genomes of different ethnic groups would be very different. They aren't.

    3. Neutral drift is the major story in how ethic groups' genomes differ.

    This pretty much follows the contours of the current orthodoxy in population genetics (with certain distinct exceptions).

    So are these three points meaningfully true?

    1. Human genomes tend to cluster into three groups: african, eurasian, and east asian.

    Generally speaking they /do/ cluster this way. Of course, you can make room for as few or as many clusters as you want-- if it was two, it'd be african/everything else. Three, african/eurasian/east asian. Four, perhaps african/eurasian/east asian/naitive american. Five, perhaps west african/east african/eurasian/east asian/naitive american. From what I've read, the most elegant statistical clusters arise when you allow for four groups (splitting native americans off from east asians). Of course, this clustering gets more complex when you consider admixture populations (e.g., the majority of south america and mexico).

    2. We expected that the genomes of different ethnic groups would be very different. They aren't.

    It's hard to say this is true or false yet, because we simply don't know how functionally significant these differences are. Two genomes may look very similar, yet be very different in many very significant ways.

    3. Neutral drift is the major story in how ethic groups' genomes differ.

    This is code for a very contentious question-- are ethnic differences merely skin-deep? The fact is, we don't know yet. There's a lot of research that points to yes; there's a lot of research that points to no. The answer to this is undoubtedly going to turn out to be: yes and no, depending on the context and the threshold you look at.

  • by JeffSh ( 71237 ) <jeffslashdot@@@m0m0...org> on Wednesday June 24, 2009 @07:25PM (#28460533)

    I take a general offense to the nature of this article, presenting this as though it is some sort of surprise. Researches along time ago classified people into 3 groups and this is merely genetic confirmation of the original findings. They classified people in 3 groups a long time ago, I suppose this is DNA confirmation of the initial categories: Negroid, Mongoloid, Caucasoid.

    non-PC names these days I suppose, but that's what they were called.

  • by Old Wolf ( 56093 ) on Wednesday June 24, 2009 @07:28PM (#28460577)

    Hasn't this been known for a long time? TFA described the three groups but didn't use these terms -- rampant political correctness, sigh..

  • by schwaang ( 667808 ) on Wednesday June 24, 2009 @07:40PM (#28460701)

    I'd add a fourth point that to me is even more interesting (and apparently comes from the data):

    As a result [*] African populations today have greater genetic diversity -- more variants in more genes -- than Eurasians or East Asians, and Eurasians somewhat more than East Asians.

    * [The population split away from Africa 70K years ago, and then that sub-population splitting again 40K years ago into Eurasian and East Asian groups. The African source population is 130K years old.]

  • by MichaelSmith ( 789609 ) on Wednesday June 24, 2009 @07:41PM (#28460713) Homepage Journal
    Advances in communication and transportation in the last century mean that members of these three groups are migrating away from the areas their ancestors lived in. I live in Australia but my ancestors came from England. My wife was born in Malaysia but her ancestors came from China. Our son is a mix of two of the groups defined by TFA.

    Yesterday he brought home a school project to work on. Each child in the class has to fill in a page in a scrap book about themselves. His classmates come from England, Spain, China, Egypt, Australia (one Aboriginal boy) and Turkey. The next generation here will be even more mixed than the last.
  • Re:I don't think so (Score:5, Interesting)

    by interkin3tic ( 1469267 ) on Wednesday June 24, 2009 @07:44PM (#28460737)

    There's the problem of one man starting a whole new population would lead to inbreeding for a while, so that's the bigger problem. But if that happened and maybe Noah and his wife/wives didn't have any negative recessive genes, or the inbred populations didn't die off, or if you fiat it away (as theists often do), then it's totally possible for three initially identical subpopulations to diverge over many generations.

    If Noah's sons all looked alike and went to different corners of the earth, it's still possible for black populations, white populations, and east asian populations to arise.

    There's still that bigger inbreeding problem. And the total lack of real evidence. And maybe not enough time for that to actually happen with a strict interpretation of the torah/old testament/whatever.

    It is interesting whenever science finds something and you can find something in holy literature that can seem to be a metaphor for it. Carl Sagan pointed out how the evolution of the human brain, the neocortex specifically, paralells the story of the apple of knowledge in interesting ways. Increased neocortical mass may be what really seperates us from animals, gives us shame and self consciousness, and interestingly may cause labor pains for women. Interesting, but it would be a mistake of course to interpret that as evidence for anything.

    Obviously, no one should take that as proof of anything, as you can interpret anything you want. Still, it is interesting.

  • by zarzu ( 1581721 ) on Wednesday June 24, 2009 @07:53PM (#28460833)
    i hope not long, blends of different races are generally some of the most beautiful people, i am very much looking forward to the widespread crossbreeding that is our future.
  • Re:Really? (Score:5, Interesting)

    by hedwards ( 940851 ) on Wednesday June 24, 2009 @08:05PM (#28460941)
    Not really, humans as a species are just about as homogeneous as you're going to get, which makes it difficult to make those sorts of claims stick. Just as much of suggesting that Africans are inferior as superior. Additionally, there's been some research to suggest that African populations have more genetic diversity than other groups, which I wouldn't think would contribute to the suggestion that they're any more or less well adapted than other groups.

    But then again, if it drives white supremecists nuts, why bother arguing. ;)
  • by Anonymous Coward on Wednesday June 24, 2009 @08:25PM (#28461095)

    Three Sons of Noah [wikipedia.org] are supposed to be the ancestors of us all.

    Ya, blah blah.

    I saw a recent study of DNA from around the planet, and tied in with some paleontology. Remember that whole "homo sapien came from the Fertile Crescent, long after the other sapien varients were gone" theory? Turns out (like most logically people suspected) that it's pretty much B.S.
    We've made some recent finds that show that homo sapien did indeed live at the same time several other Homo variants were alive. The immediate response by the "fertile crescent" proponents simply said "well, then the Homo sapiens must have just killed the ones they ran into. all of them, completely wiped out.". To which the logical people said "bullshit".

    Welp, turns out after doing some even more recent DNA testing, that Homo Sapiens probably didn't wipe out the other Homo variants at all- they had sex with them & absorbed them over time into their own genetic pool. A good bit of the regionalized diversity amongst homo sapiens is due originally to which other Homo variants were in that general region.

    So no, we didn't come from "the fertile crescent". Homo sapiens are a result of several different Homo variants breeding with other variants, so we don't HAVE a common point of origin for our species. Which makes a hell of a lot more sense than the idea that we just suddenly showed up and sprouted an entire diverse genetic pool from two people, or three, etc.

  • by langelgjm ( 860756 ) on Wednesday June 24, 2009 @08:41PM (#28461231) Journal
    Well, one of the moderations was "redundant", which is fair since someone mentioned the same thing again. But yeah, I think there's some general ignorance surrounding those terms - people think "Negroid" is a slur (just like that politician a few years ago who got lambasted for saying "niggardly"). From wikipedia: [wikipedia.org]

    In physical anthropology the term is one of the three general racial classifications of humans â" Caucasoid, Mongoloid and Negroid. Under this classification scheme, humans are divisible into broad sub-groups based on phenotypic characteristics such as cranial and skeletal morphology. Such classifications remain in use today in the fields of anthropology and forensics to help identify the ethnicity, lineage and origin of human remains.

  • It's Obvious. (Score:4, Interesting)

    by TrevorB ( 57780 ) on Wednesday June 24, 2009 @09:03PM (#28461385) Homepage

    Humans, Cylons, and descendants of the aboriginals of this planet.


  • by jd ( 1658 ) <{moc.oohay} {ta} {kapimi}> on Wednesday June 24, 2009 @09:40PM (#28461639) Homepage Journal

    The San people (one of the first to split off from the earliest-known haplogroup) are supposed to have one of the greatest levels of genetic diversity of any of the African groups, which themselves are, as you say, generally more diverse than those that left Africa.

    So, to get good genomic data from these people, you have to sample a lot more of them to get an accurate picture. I wonder if the researchers took that into account.

    Oh, another point of interest. The earliest known religious structure in Africa is also 70K years old. Maybe Africans got fed up with them and kicked them out, the way the Europeans did with the Pilgrims.

  • by Anonymous Coward on Wednesday June 24, 2009 @10:13PM (#28461881)

    Totally. Afterall we've got our own modern age myths. Our creation myth is "a big bang happened, and then a bunch of really good luck occurred." Our Hell, what we tell our children is the result of living a "sinful" life, is the global warming fable. Plus other popular myths like socialism is sustainable, and a baby we can't see is not-a-baby. What quaint little ignorant brutes we always remain.

  • by Anonymous Coward on Wednesday June 24, 2009 @10:14PM (#28461885)

    Please explain this inbreeding problem thingy.

    The way I understand it, inbreeding is a problem because of mutations in our genes.. with two different genes in the same place, the non-broken one can make up for the mutated one, but with inbreeding there's no redundancy.

    Perhaps Noah's offspring hadn't evolved enough to have these corrupted genes - in that case, there wouldn't be a problem. (If I recall correctly there wasn't any law against marrying siblings until way later)

  • by unfasten ( 1335957 ) on Wednesday June 24, 2009 @10:36PM (#28462099)

    Couldn't a scientist fall under all 3 of those?

    Makes things happen: initiate a chemical reaction
    Lets things happen: watch what happens after initiating said chemical reaction
    Ask "What the hell just happened?" when something unexpected happens and then they try to find out.

  • by rs79 ( 71822 ) <hostmaster@open-rsc.org> on Thursday June 25, 2009 @12:11AM (#28462711) Homepage

    " Every study done over the last two decades shows that H. sapiens sapiens did *NOT* interbreed with Neandertals or other Hominids."

    The studies done recently however suggest otherwise.

    http://news.nationalgeographic.com/news/2007/08/070802-neanderthals.html [nationalgeographic.com]

  • Re:Really? (Score:3, Interesting)

    by quarterbuck ( 1268694 ) on Thursday June 25, 2009 @02:06AM (#28463295)
    Actually the summary is Bullshit. And the story ignores a bunch of details. Look at the graphic [washingtonpost.com] associated with the study . They study 3 genes - two of which affects skin/hair color and another that affects the eye color. Then they find that these 3 genes mutate into 3 different groups. I don't think this study in anyway shows anything more than show a genetic basis to skin/hair/eye color.
  • by eosin ( 1582843 ) on Thursday June 25, 2009 @02:53AM (#28463507)
    It wasn't that long ago that Anthropology texts said the same basic thing, dividing humanity into three groups called Caucasoid, Negroid, and Mongoloid. Then such texts were considered outdated, and worse. Now it appears to have come full circle, with exhaustive scientific investigation apparently verifying what earlier generations noted from simple observation. Of course, 'What It All Means(TM)' for us today is another matter entirely.
  • Re:Read the Bible. (Score:3, Interesting)

    by TheRaven64 ( 641858 ) on Thursday June 25, 2009 @05:23AM (#28464247) Journal
    Virgin birth is a relatively new idea. The immaculate conception meant that he was born without original sin, not without intercourse. As I recall, this was one of the things introduced at the Council of Nicea, where they tried to reconcile a few hundred incompatible versions of Christianity into one version; think of it as theological POSIX. As for burning bushes, I expect you'd be talking to burning bushes if you had to live in the desert for long...
  • by malkavian ( 9512 ) on Thursday June 25, 2009 @05:24AM (#28464255)

    The future of 'racism' is that word will fall out of fashion and pretty much cease to exist in a generation or so. It's hideously divisive in a modern context.
    At the start, where there was a serious belief in the western world that being non-caucasian meant you were sub-human, then the laws necessary to stop that were a boon.
    Now, anything gets shoved under the context of 'racism' that's meant to cause a knee jerk reaction.
    Say something about someone who was born in Ireland? Racist (their parents may have come from just down the road from you, but hey, 'racist')! Nobody from an 'ethnic group' turns up for interviews for jobs at your company for particular roles? Hey, you're not hiring enough of them, so you're racist.
    The worst thing about the modern "positive discrimination" isn't that it's actually the most prevalent form of racism at the moment, it's that it actually intimates that someone from an ethnic background isn't capable of performing well enough to compete against anyone else, and "allowances" have to be made for them. Filtering back into schools, there's a whole sector of kids that know they'll get jobs allocated to them under this, so don't consider it worth pushing themselves as hard to compete (some of my family work in the school system, and this drives them nuts!).

    Face it, people are people, and some people don't like others for a variety of reasons. Mannerisms, attitude, so on, so forth. The way this used to be dealt with was a little thing called Etiquette, which for some reason seems to be considered horribly old fashioned and outdated these days. The basic principle was that you knew other people were flawed, in the same way you knew yourself to be flawed. Yet everyone needed to keep on going without killing each other. So you looked for the best in people, and given the chance chose to accept something as complimentary rather than derogatory (or at least did so at face), and you exchanged pleasantries, no matter how the barb ran underneath that.

    Now, taking offense is an industry. If you can find a way to take offense to something someone says, there's a quick bit of cash to be had through a Lawyer somewhere who specialises in that. Taking offense on behalf of someone else (who frequently isn't offended at all anyway) is the way to obtain a false sense of self worth. Sure, it makes you feel good (after all, you're looking after "the children"/"some group that can't look after themselves"/"some other group that you're better, and more able than"). It puts you subjectively above them, even if that's not what you think you're doing.

    When science comes up with these figures, it is NOT a method of saying "hey look, food for bigots". It is stating an observable fact. Anything beyond the figures is conjecture. There are three main branches of humanity that have been successful in evolutionary terms. That's possible failsafes in case there's a flaw in one or more branches of the genetic structure that some pathogen can take advantage of. It's a good thing.

    If you instantly think of 'racism' over released figures, I think you're part of a longer, more insidious issue than ever these figures could be.

  • by TheRaven64 ( 641858 ) on Thursday June 25, 2009 @06:12AM (#28464447) Journal
    I take it you don't believe in police forensics either?
  • Re:I don't think so (Score:5, Interesting)

    by dalutong ( 260603 ) <djtansey@gmail . c om> on Thursday June 25, 2009 @07:22AM (#28464675)

    Though the Chinese government has its faults, I don't think your statement, "a nation's Government is the single largest institution that decides its prosperity," disqualifies China from continuing its rise. The government is very aware of what will allow China's continued economics rise. This can be seen with some of the long-term partnerships China has developed with countries around the world. It is slowly learning how to implement a civil society without ensuring its own destruction.

    But I disagree with your statement more generally, too. As ElectricTurtle said, East Asia, especially China, was on top of the world for about a millennium. And they didn't do it under a democracy. They did it because China has the world's oldest tradition of a meritocracy. Since Confucius, the way you made it up in the world was through passing an exam. That's why China has been able to rise so quickly -- the people value education, and are willing to sacrifice everything so that their children might have more.

    I wanted to add one more example to ElectricTurtle's list. China had ships that could carry 15x the tonnage as Christopher Columbus' ships almost a century before he "discovered" America. And they were much harder to sink because they had separate compartments around the base of the ship. If one was punctured and flooded, they could keep sailing. Why didn't they become the great explorers then? Two reasons. One, China was the center of the world and so they weren't so interested in exploring. And two, the internal culture just happened to become xenophobic just as Zhenghe's (the admiral of the ships described above) era of exploration was coming to an end. (And, under the next dynasty, run by the Mongols, there was an effort to appease the Chinese by sticking to their traditions. This impeded progress. Sort of like if the U.S. all became Amish.)

    To further cast doubt on the manifest destiny that "inevitably" lead to Europe's rise, consider this. The Europeans were brutal to those they colonized. They demanded submission and subservience. During Zhenghe's day, the Chinese didn't. They created trade pacts, but let the people be. So what might have happened if the wheels of development had been a little more favorably aligned for the Chinese (and all other non-Europeans?) What if Zhenghe had been alive at the time of Columbus? Do you think the people of the world would have rather dealt with the European colonizers or partnered with the must more respectful Chinese?

    Note: a fun model comparing Zhenghe's treasure ships to Columbus'. http://upload.wikimedia.org/wikipedia/commons/thumb/1/10/Zheng_He's_ship_compared_to_Columbus's.JPG.jpg/800px-Zheng_He's_ship_compared_to_Columbus's.JPG.jpg [wikimedia.org]

Karl's version of Parkinson's Law: Work expands to exceed the time alloted it.