Thursday, October 08, 2009

The Problem of Race .... Again

 
The current politically correct view of human races is that they don't exist. Surprisingly, this view has been adopted by many scientists, including biologists, who should know better.

Bruce T. Lahn and Lanny Ebenstein have published an opinion piece in this week's issue of Nature. Everyone should read it [Let's celebrate human genetic diversity].

They begin by pointing out the problem and then they state their position.
The current moral position is a sort of 'biological egalitarianism'. This dominant position emerged in recent decades largely to correct grave historical injustices, including genocide, that were committed with the support of pseudoscientific understandings of group diversity. The racial-hygiene theory promoted by German geneticists Fritz Lenz, Eugene Fischer and others during the Nazi era is one notorious example of such pseudoscience. Biological egalitarianism is the view that no or almost no meaningful genetically based biological differences exist among human groups, with the exception of a few superficial traits such as skin colour3. Proponents of this view seem to hope that, by promoting biological sameness, discrimination against groups or individuals will become groundless.

We believe that this position, although well-intentioned, is illogical and even dangerous, as it implies that if significant group diversity were established, discrimination might thereby be justified. We reject this position. Equality of opportunity and respect for human dignity should be humankind's common aspirations, notwithstanding human differences no matter how big or small. We also think that biological egalitarianism may not remain viable in light of the growing body of empirical data (see box).
These guys seem to be a bit late in realizing that the scientific data doesn't support the politically correct "biological egalitarianism" viewpoint but, as they say, better late than never.

Here's their bottom line.
  • Promoting biological sameness in humans is illogical, even dangerous
  • To ignore the possibility of group diversity is to do poor science and poor medicine
  • A robust moral position is one that embraces this diversity as among humanity's great assets
Bravo! I'm glad that more and more scientists are speaking out on this issue.


Lahn, B.T. and Ebenstein, L. (2009) Let's celebrate human genetic diversity. Nature 461:726-728 [Nature]

[Hat Tip: Nils Reinton at BIOpinionated: I Wish I Wrote This (me too! -LAM)]

29 comments :

  1. It's always delightful when you find yourself agreeing with someone on a contentious point.

    To ignore human genetic diversity is illogical at the very least and poor science at worst.

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  2. Nice essay - I've been puzzled for a while now with the likes of Greg Laden, who insist that races don't exist. It's true that delineating people into groups is futile and even dangerous, but it's also true that haplotypes map onto human populations and human diversity is quite impossible to overlook.

    So, nice article by Lahn and Ebenstein.

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  3. Please forgive the lack of a reference; this is all from memory, but if I'm not mistaken (and someone please correct me if I'm wrong) the basis of the claim is not that genetic differences between human groups don't exist, the claim is that the traditional divisions are misleading or meaningless. There is in fact more genetic diversity between groups in sub-Saharan Africa (all of which are are traditionally grouped under the label "black" or "African") than between all the other traditional racial groups.

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  4. The thing that baffles me on this topic is the inability of so many scientists to keep two thoughts in their head at once. Specifically: humans have genetic diversity AND human races do not exist (at a genetic level).

    Why that gives so many people so much trouble, I don't know.

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  5. I always understood the "race has no biological basis" argument the way Bill Gascoyne describes it - it's not that there aren't meaningful biological differences between human populations. Instead it's that the way society groups people into "races" isn't biologically meaningful.

    For example, here in the US, anyone with visible African ancestry is categorized as "black", no matter what part of Africa his ancestors lived in, or whether his ancestry is actually predominantly European.

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  6. peggy, but it is. the genomic data suggest that only 10% of african americans are 50% or more european in ancestry (median being 20%). so the social construct maps really well onto two populations, one which is mostly african, and one which has very little non-european (and more of that might be native american than african).

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  7. All correct, of course, but still embellished with lots of PC insignia:

    "Genetic diversity is a strength not a weakness
    of humanity. It is time to acknowledge, embrace and celebrate this strength".


    Strictly speaking, that's bullshit. If it turns out that genetic diversity extends to group differences in cognitive abilities, it is most certainly a weakness of humanity. But even then, if it really is a fact, there is little choice but to acknowledge and accomodate it.

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  8. Peggy says,

    I always understood the "race has no biological basis" argument the way Bill Gascoyne describes it - it's not that there aren't meaningful biological differences between human populations. Instead it's that the way society groups people into "races" isn't biologically meaningful.

    For example, here in the US, anyone with visible African ancestry is categorized as "black", no matter what part of Africa his ancestors lived in, or whether his ancestry is actually predominantly European.


    It's political correctness masquerading as science.

    You don't deny the existence of biological races just because some people in the USA are racists and misuse the term. That's what many scientists have been doing for the past few decades.

    It's no way for a real scientist to behave.

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  9. Larry: it's not just "some people in the US" that discuss race in that way, it's the standard American English usage. I guess I'm only familiar the "race is not real" discussion in the context of popular science writing (and programming) where it's basically it's a substitute for a more nuanced discussion of whether the sociological usage of the term "race" matches up with what biologists mean when they are discussing genetic differences between populations.

    I don't think the research topics should be dictated by what racists and other people ignorant of genetics think, but there is is so much cultural and emotional baggage around "race" - not just for the general population, but for scientists too - that it's worth treading carefully in terms of language choice.

    Razib: I think the significance of that variation depends on what sort of scientific argument you are trying to make. It's not just that the African-American population has a median of %20 or so European Ancestry, it's that there is significant variation in ancestry within the African American population. To my mind that makes it difficult to apply generalizations about the genetic makeup of the population to individual African Americans, which is what I think most of the "biological egalitarianism" talk boils down to.

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  10. but - I always thought the concept of races only make sense in a country like US, where many populations with relatively recent ancestry are mixed together (and it is relatively easy to distinguish between them based on genomic data). If you look at a bigger picture, however, human genetic diversity is continuous, and thus you cannot really divide it into 'races' (or into anything for that matter) , because any such division will be totally arbitrary. This has been the basis of my 'there are no races' statement, but can anyone could enlighten me on this?

    And just to make it clear - it does make a lot of sense to divide people up regarding their response to some drug, predisposition to some disease etc, and use this information in medicine. But I wouldn't call these groups races at all, and I do have a feeling that anytime anyone who talks about races s/he talks about slightly different thing.

    cheers!

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  11. Eh, sorry for the poor writing, blogger's comment submission form is really crappy.

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  12. @ Larry for answering Peggy
    That was an ideological answer! Let us talk science please!!! Peggy made a scientific argument and by the way she and Bill got it right.

    and yes there is diversity......

    @DK
    diversity in evolutionary terms is not a strength, but a must!

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  13. Bill is using Lewontins famous point that there is much more genetic variation between members of the same 'racial' group than between members of that group and another group.
    For some reason this point seems to equate to "there are no genetic differences between different racial groups" to certain individuals. The fact that perhaps 15% of a persons variation may be 'race' specific is plenty of space for biologically important differences - the most obvious ones, apart from superficial skin color, being alleles for traits like lactate tolerance and sickle cell anemia.
    If you think there are no biological differences then ask yourself this question. Would it be possible to perform a biological test that will accurately assign an individual to a self described racial group with a confidence of say 95%?
    This sort of test would be entirely consistent with Lewontins original claim but provides results that confirms or denies the self designation. If it confirmed the self designation do you think there could be a better explanation than it being due to real biological differences?

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  14. Perhaps germane:

    http://sciencenow.sciencemag.org/cgi/content/full/2009/1008/3

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  15. Dang, the URL in my previous comment was cut off. It's a summary of some just-published research showing Homo sapiens went through a couple of genetic bottlenecks ~60-50K years ago, reducing diversity in the population outside Africa.

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  16. r-evolution73 says,

    That was an ideological answer! Let us talk science please!!! Peggy made a scientific argument and by the way she and Bill got it right.


    They did not make a scientific argument.

    There are many scientist who argue that races don't exist in Homo sapiens. Bill and Peggy did not address that argument. Instead, they said that some people deny the existence of races because members of the general public behave stupidly when making racial assignments.

    How is that a scientific argument?

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  17. Peggy says,

    Larry: it's not just "some people in the US" that discuss race in that way, it's the standard American English usage.

    Sorry about that. Let me rephrase my response to see if you agree.

    "Scientists in other countries don't deny the existence of biological races just because most people in the USA are racists and misuse the term 'race.'"

    Is that better?

    I don't think the research topics should be dictated by what racists and other people ignorant of genetics think, but there is is so much cultural and emotional baggage around "race" - not just for the general population, but for scientists too - that it's worth treading carefully in terms of language choice.

    I don't think political correctness should dictate the proper use of scientific terms like "race."

    The word has a scientific meaning and it's silly to deny the existence or human races just because the word is a very sensitive one in some countries.

    However, let's try a little experiment and see where it gets us. Do you think the human species is subdivided into genetically distinct populations? Do you think it's possible for a forensic scientist to assign people to one of these populations based on their DNA fingerprint? (1)

    See, I avoided the "r" word in order to find out whether that's really what's bothering you.

    1. Please don't quibble about whether the assignment is always 100% accurate. We all know about individuals that have genes from two or more different populations due to outbreeding. That's why they're populations and not species.

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  18. DK says,

    All correct, of course, but still embellished with lots of PC insignia:

    "Genetic diversity is a strength not a weakness of humanity. It is time to acknowledge, embrace and celebrate this strength".



    Good point. The issue has become so sensitive that the authors felt it necessary to declare that they are not racists.

    It's sad, really, but I understand their problem. There are "scientists" out there who are more than willing to accuse someone of racism if they dare to defend the idea of biological races.

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  19. The word has a scientific meaning and it's silly to deny the existence or human races just because the word is a very sensitive one in some countries.

    Just to expound in this and to preempt some of the objections:

    Given the difficulties of defining even species, it should not be surprising that definition of "race" is not set in stone. (That does not of course mean that species and races/subspecies don't exist).

    Among many existing definitions, a lot of them by famous biologists, one, IMHO, stands out as the best. It is from American Heritage Dictionary of the English Language and it is surprisingly accurate and works much better than numerous attempts by recognized experts:

    Race (Biology)
    1. An interbreeding, usually geographically isolated population of organisms differing from other populations of the same species in the frequency of hereditary traits. A race that has been given formal taxonomic recognition is known as a subspecies.


    One has to be absolutely insane (like Greg Laden) to deny that races as defined above don't exist. (He actually did deny it with a lame attempt to claim there was never a geographical isolation. Apparently, that's how they teach you in Harvard).

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  20. I guess I should have made clear that I wasn't trying to make a scientific argument, exactly.

    I don't have online access to Nature so I don't know what papers the op-ed was referring to where biologists made the argument that there is no significant genetic difference between different human populations. That certainly would be unscientific.

    Sure the human population can clearly be subdivided by their genetic makeup, both into large groups and into smaller more closely related subpopulations.

    But the unfortunate reality is that there is a long history of biology being misused to lump all individuals in a population together as a "race" with identical characteristics. It would be great if people clearly understood that it meant that a biological race simply "differs from other in the frequency of hereditary traits", but most don't get that having a higher probability of carrying a hereditary trait does not mean that that person necessarily carries that trait. And I think it's perfectly valid to tell people that human genetic variation is more complicated than that.

    So yeah, I guess that's "political correctness", but the term "race" has so much historical and social baggage, I don't think it's actually a particularly useful term for scientists to use when talking about human genetic variation.

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  21. Peggy said : << Sure the human population can clearly be subdivided by their genetic makeup, both into large groups and into smaller more closely related subpopulations. >>

    I desagree. The human population can NOT clearly be subdivided by their genetic makeup.
    If this is what some people pretend that races are, then obviously races do NOT exist as a scientific entity in the situation of modern Homo sapiens.

    Of course, Mister Moran is always maintaining the confusion << races = any kind of group/subdivision >> and all his mental horizon is based on that claim.

    I'm sorry, but this claim is ridiculous. The semantic confusion between races and for instance subspecies, or populations, is cultivated by Moran in this topic, and all the others about the same polemic. But those objects (subspecies, races and populations), if they really are subdivisions, are NOT the same thing.

    By their result, they are not,. And neither by the way they are formed (for the domestic races : by endogamic selection and exclusion of the undesired characters).

    The division in "races" is not a scientific subdivision or entity in most of the species (except the domestic races, where an artificial intention of preservation/exclusion is common)..

    In this chapter, Moran is not a Sientist.

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  22. Anonymous: But you can separate groups of humans by their genotype - I think the boundaries of those groups can be fuzzy, and that those borders may be different depending on what genotype you are assaying, and that grouping by genotype doesn't necessarily match how society groups people into races - but that doesn't mean such groupings can't be made.

    (And do any biologists use the term "race" to refer to anything but humans anymore? Darwin's "races of cabbages" always sounded strange to me.)

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  23. i always feel in these discussions people are talking past each other, especially when they have differing definitions of words like 'race'. so to clarify matters for me, i would like Dr. Moran to give the likely number of races that currently exist, say something on the stability of such groupings,give examples (if possible) of these racial groupings along with their differing genetic markers e.g. race 1 - geographically located in region A & B, with unique (almost Unique) gene combination 1,3,4,5 occuring at frequencies A,B,C,E.

    this would then make it exceeding clear where the differences and similarities between a popular cultural understanding of race and a biological understanding lie.

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  24. "Where is the beef?"

    In the paper I can not find any mentioning of the term 'race' at all!!! Some people show some obsession regarding the term race.
    It reminds me of Pavlov's dog.
    Sorry, but it does!

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  25. science:

    What scientist would seriously state that there is no genetic diversity in the human population? No one! This is not a matter of debate at all, but the authors seem to pretend it is. Then they go and pretend to break this non-existing hypothesis just to claim that the selectionist bias of their paper is right. This in fact is where there is debate and data lean towards "random drift at neutral loci" (Ref.5).

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  26. Peggy:
    But you can separate groups of humans by their genotype - I think the boundaries of those groups can be fuzzy

    Yes, it is very easy to separate groups of humans by their genotypes with very high precision.
    The fuzzy boundaries are natural and don't mena the groups don't exist. Much the same way that color "green" exists.

    and that those borders may be different depending on what genotype you are assaying

    That's why many markers have to be used simultaneously.

    and that grouping by genotype doesn't necessarily match how society groups people into races

    That's irrelevant. The discussion is about biological races, not any other numerous meanings of the word.

    And do any biologists use the term "race" to refer to anything but humans anymore?

    They do it all the time. In phytopathology, particularly outside North America, "race" is a comon handle for "polulation" or "strain" of fungal pathogens.

    Then there are races of bees, in common usage to this day.

    Darwin's "races of cabbages" always sounded strange to me.

    How they sound to you is irrelevant. The issue is whether they are real.

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  27. DK said :
    << Race (Biology)
    1. An interbreeding, usually geographically isolated population of organisms differing from other populations of the same species in the frequency of hereditary traits. A race that has been given formal taxonomic recognition is known as a subspecies.

    One has to be absolutely insane (like Greg Laden) to deny that races as defined above don't exist. (He actually did deny it with a lame attempt to claim there was never a geographical isolation. Apparently, that's how they teach you in Harvard). >>


    The point here is that we do not have the same understanding of what "Race" means, and I also disagree with races => subspecies, cos the consequence of those objects is quite different in the genetic pool.

    Let's see another vision :

    Races:
    Varieties of the [strain] species with limited genetic pool, issued of artificial selection processes * successive endogamic crosses * strict artificial reproductive isolation maintained with the natural strain and with other varieties.
    Resultant: trends towards 1:1 homozygosity and 1:1 close genetic interindividuals.

    Subspecies:
    mostly geographical varieties of the species (still interbreeding) from relative genetic isolation (often geographic) * environmental conditions / promoting progressive development of inter distinctiv characters.
    Resultant: hypothetical tendency to speciation (not completed), with preservation of genetic polymorphism in the group.

    If you consider that here, subspecies end races are quiet different, then you'll agree that race is not adapted to the situation allelic human populations, neither to the way Those people are

    If you integrate that through this extremely punctilious definition under a view of population genetics, the term defined by race does not apply to the allelic status of human populations norc even to how they are a result of very different processes, then should understand the semantic but very factual point wich is mine : the term race here is not valid nor to understand the palogeographic history of Homo sapiens and its poipulations, neither to understand the phylogeographic resulting.

    Of course, if like Moran you assimilate "Races" to any subdivision, in this case is useless to continue the discussion.

    Best regards

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  28. Larry can you tell me why the paper promted a discussion about race? Was it the picture in it?

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