Monday, January 30, 2006

Race - Fact Or Fiction?

The excellent Mixing Memory recently had a post commenting, prompted by some comments from Fido the Yak, on MIT cognitive psychologist and best-selling author Steven Pinker’s remarks about group differences in his answer to the Edge Annual question. It’s a little old now, but I thought the questions they raised about Pinker’s comments, and the notion of race, provided reason enough to say a little these ideas, and to clear up some confusion.

Fido says, “I believe [Pinker’s] a sexist, a racist and willfully ignorant of certain facts of evolutionary science” (these are serious charges that warrant careful substantiation); Mixing Memory adds, “First of all, Fido gets Pinker exactly right. As I've said many times, Pinker has a nasty habit of speaking authoratatively about topics on which he is anything but an authority (like, say, gender differences in mathematical ability)… Like Pinker, I'm not an expert in genomics, or anything remotely related to genetics, but unlike Pinker, I'm not going to comment on the issues discussed in the forum as though I am an expert.” Both Mixing Memory and Fido mention a recent forum on race, where the experts set the record straight on race, supposedly. When Fido says, “when I want to learn about population genetics, I consult a population geneticist, Luigi Luca Cavalli-Sforza, for instance, who would give me plenty of reasons to doubt that what Pinker says approximates anything I should pay attention to”, he gives the impression that the weight of expert opinion refutes Pinker. But it doesn’t take much searching to challenge this idea (and NOT [D.J. important corrective word added] through selective picking of contrarian, fringe experts), and in this post I’ll let the experts speak for themselves.

In 2002, Daedalus published two essays, one by Ernst Mayr, the other by James Crow, both on race.

Mayr was until his death the doyen of American evolutionary biology, and one of the architects of the evolutionary synthesis. This doesn’t make him infallible, but he’s not a crank either. Here’s some selected quotes from his essay:
“There is a widespread feeling that the word “race” indicates something undesirable and that it should be left out of all discussions. This leads to such statements as “there are no human races”. Those who subscribe to this opinion are obviously ignorant of modern biology. Races are not something specifically human; races occur in a large percentage of species of animals … The terms “subspecies” and “geographic races” are used interchangeably in [the] taxonomic literature.”
James Crow is a distinguished and widely respected population geneticist; here’s some more extensive quotes from his essay:
“If we randomly choose a pair of bases from corresponding sites in two persons, 99.9 percent of the time they will be the same. This percentage depends only slightly on whether the two people are from the same or from different continents, from the same or from different population groups … Analysis of DNA allows us to measure with some precision the genetic distance between different populations of human beings. By this criterion, Caucasians and Asians are relatively similar, whereas Asians and Africans are somewhat more different. The differences between the groups are small–but they are real … Just as there are great differences among individuals, there are average differences, usually much smaller, between groups. Italians and Swedes differ in hair color. Sometimes the differences are more conspicuous, such as the contrasting skin color and hair shape of Africans and Europeans. But, for the most part, group differences are small and largely overshadowed by individual differences. Biologists think of races of animals as groups that started as one, but later split and became separated, usually by a geographical barrier. As the two groups evolve independently, they gradually diverge genetically. The divergences will occur more quickly if the separate environments differ, but they will occur in any case since different mutations will inevitably occur in the two populations, and some of them will persist… In much of the animal world, however, and also in the human species, complete isolation is very rare. The genetic uniformity of geographical groups is constantly being destroyed by migration between them. In particular, the major geographical groups – African, European, and Asian – are mixed, and this is especially true in the United States, which is something of a melting pot. Because of this mixing, many anthropologists argue, quite reasonably, that there is no scientific justification for applying the word “race” to populations of human beings. But the concept itself is unambiguous, and I believe that the word has a clear meaning to most people. The difficulty is not with the concept, but with the realization that major human races are not pure races. Unlike those anthropologists who deny the usefulness of the term, I believe that the word “race” can be meaningfully applied to groups that are partially mixed. Different diseases are demonstrably characteristic of different racial and ethnic groups. Sickle cell anemia, for example, is far more prevalent among people of African descent than among Europeans. Obesity is especially common in Pima Indians, the result of the sudden acquisition of a high-calorie diet to which Europeans have had enough time to adjust. Tay-Sachs disease is much more common in the Jewish population. There are other examples, and new ones are being discovered constantly. The evidence indicating that some diseases disproportionately afflict specific ethnic and racial groups does not ordinarily provoke controversy. Far more contentious is the evidence that some skills and behavioral properties are differentially distributed among different racial groups. There is strong evidence that such racial differences are partly genetic, but the evidence is more indirect and has not been convincing to everyone.”
We can at least conclude from these comments that the concept of race is not dismissed by all serious biologists; for sure, scientists such as Richard Lewontin and others reject the usefulness of the concept of race, but that view doesn’t win by default. Straight off we should be suspicious of the quick dismissal of the concept of race, and also the charge that Pinker is being ignorant, willfully or not, of evolutionary science. He might not agree with Lewontin and company, but that doesn’t automatically make him wrong.

However, without some clarification and qualification the claims of Mayr and Crow might be objected to (even with the clarifications and qualifications the claims might still be objectionable to some – reasonable people can disagree!). Here’s how Steve Olson and Michael Bamshad begin an article entitled ‘Does Race Exist?’ in Scientific American:
“Look around on the streets of any major city, and you will see a sampling of the outward variety of humanity: skin tones ranging from milk-white to dark brown; hair textures running the gamut from fine and stick-straight to thick and wiry. People often use physical characteristics such as these-along with area of geographic origin and shared culture--to group themselves and others into "races." But how valid is the concept of race from a biological standpoint? Do physical features reliably say anything informative about a person's genetic makeup beyond indicating that the individual has genes for blue eyes or curly hair?
The problem is hard in part because the implicit definition of what makes a person a member of a particular race differs from region to region across the globe. Someone classified as "black" in the U.S., for instance, might be considered "white" in Brazil and "colored" (a category distinguished from both "black" and "white") in South Africa.

Yet common definitions of race do sometimes work well to divide groups according to genetically determined propensities for certain diseases. Sickle cell disease is usually found among people of largely African or Mediterranean descent, for instance, whereas cystic fibrosis is far more common among those of European ancestry. In addition, although the results have been controversial, a handful of studies have suggested that African-Americans are more likely to respond poorly to some drugs for cardiac disease than are members of other groups.

Over the past few years, scientists have collected data about the genetic constitution of populations around the world in an effort to probe the link between ancestry and patterns of disease. These data are now providing answers to several highly emotional and contentious questions: Can genetic information be used to distinguish human groups having a common heritage and to assign individuals to particular ones? Do such groups correspond well to predefined descriptions now widely used to specify race? And, more practically, does dividing people by familiar racial definitions or by genetic similarities say anything useful about how members of those groups experience disease or respond to drug treatment?

In general, we would answer the first question yes, the second no, and offer a qualified yes to the third.”
The authors then go on to discuss some specific studies:
“One of us (Bamshad), working with University of Utah scientists Lynn B. Jorde, Stephen Wooding and W. Scott Watkins and with Mark A. Batzer of Louisiana State University, examined 100 different Alu polymorphisms in 565 people born in sub-Saharan Africa, Asia and Europe. First we determined the presence or absence of the 100 Alus in each of the 565 people. Next we removed all the identifying labels (such as place of origin and ethnic group) from the data and sorted the people into groups using only their genetic information.

Our analysis yielded four different groups. When we added the labels back to see whether each individual's group assignment correlated to common, predefined labels for race or ethnicity, we saw that two of the groups consisted only of individuals from sub-Saharan Africa, with one of those two made up almost entirely of Mbuti Pygmies. The other two groups consisted only of individuals from Europe and East Asia, respectively. We found that we needed 60 Alu polymorphisms to assign individuals to their continent of origin with 90 percent accuracy. To achieve nearly 100 percent accuracy, however, we needed to use about 100 Alus.

Other studies have produced comparable results. Noah A. Rosenberg and Jonathan K. Pritchard, geneticists formerly in the laboratory of Marcus W. Feldman of Stanford University, assayed approximately 375 polymorphisms called short tandem repeats in more than 1,000 people from 52 ethnic groups in Africa, Asia, Europe and the Americas. By looking at the varying frequencies of these polymorphisms, they were able to distinguish five different groups of people whose ancestors were typically isolated by oceans, deserts or mountains: sub-Saharan Africans; Europeans and Asians west of the Himalayas; East Asians; inhabitants of New Guinea and Melanesia; and Native Americans. They were also able to identify subgroups within each region that usually corresponded with each member's self-reported ethnicity.

The results of these studies indicate that genetic analyses can distinguish groups of people according to their geographic origin. But caution is warranted. The groups easiest to resolve were those that were widely separated from one another geographically. Such samples maximize the genetic variation among groups. When Bamshad and his co-workers used their 100 Alu polymorphisms to try to classify a sample of individuals from southern India into a separate group, the Indians instead had more in common with either Europeans or Asians. In other words, because India has been subject to many genetic influences from Europe and Asia, people on the subcontinent did not group into a unique cluster. We concluded that many hundreds--or perhaps thousands--of polymorphisms might have to be examined to distinguish between groups whose ancestors have historically interbred with multiple populations.

The human race
Given that people can be sorted broadly into groups using genetic data, do common notions of race correspond to underlying genetic differences among populations? In some cases they do, but often they do not. For instance, skin color or facial features--traits influenced by natural selection--are routinely used to divide people into races. But groups with similar physical characteristics as a result of selection can be quite different genetically. Individuals from sub-Saharan Africa and Australian Aborigines might have similar skin pigmentation (because of adapting to strong sun), but genetically they are quite dissimilar.”
Studying race isn’t just of mere intellectual interest – it can also prove useful in biomedicine:
“But the importance of group membership as it relates to health care has been especially controversial in recent years. Last January the U.S. Food and Drug Administration issued guidelines advocating the collection of race and ethnicity data in all clinical trials. Some investigators contend that the differences between groups are so small and the historical abuses associated with categorizing people by race so extreme that group membership should play little if any role in genetic and medical studies. They assert that the FDA should abandon its recommendation and instead ask researchers conducting clinical trials to collect genomic data on each individual. Others suggest that only by using group membership, including common definitions of race based on skin color, can we understand how genetic and environmental differences among groups contribute to disease. This debate will be settled only by further research on the validity of race as a scientific variable.

A set of articles in the March 20 issue of the New England Journal of Medicine debated both sides of the medical implications of race. The authors of one article--Richard S. Cooper of the Loyola Stritch School of Medicine, Jay S. Kaufman of the University of North Carolina at Chapel Hill and Ryk Ward of the University of Oxford--argued that race is not an adequate criterion for physicians to use in choosing a particular drug for a given patient. They pointed out two findings of racial differences that are both now considered questionable: that a combination of certain blood vessel-dilating drugs was more effective in treating heart failure in people of African ancestry and that specific enzyme inhibitors (angiotensin converting enzyme, or ACE, inhibitors) have little efficacy in such individuals. In the second article, a group led by Neil Risch of Stanford University countered that racial or ethnic groups can differ from one another genetically and that the differences can have medical importance. They cited a study showing that the rate of complications from type 2 diabetes varies according to race, even after adjusting for such factors as disparities in education and income.

The intensity of these arguments reflects both scientific and social factors. Many biomedical studies have not rigorously defined group membership, relying instead on inferred relationships based on racial categories. The dispute over the importance of group membership also illustrates how strongly the perception of race is shaped by different social and political perspectives.

In cases where membership in a geographically or culturally defined group has been correlated with health-related genetic traits, knowing something about an individual's group membership could be important for a physician. And to the extent that human groups live in different environments or have different experiences that affect health, group membership could also reflect nongenetic factors that are medically relevant.”
In June 2005, the United States Food & Drug Administration approved NitroMed’s BiDil for the treatment for heart failure in African-Americans only. This was based on data showing greater benefit in self-identified black patients. Let’s assume that there is a genetic component this difference (it’s common for genetic profiles to affect the effects of drugs, as revealed by pharmacogenetics, although it could be an environmental factor). The enhanced effect in black compared with white patients is not the result of the fact that all black individuals have one version of a given gene and all white individuals have a different one – there aren’t these discrete genetic groups. It’s just that being black, by virtue of ancestry, means that you’re more likely to possess this given genetic variant, which is the view of race validated by Olson and Bamshad. Race here is just functioning as a proxy measure of genetic identity, but it’s just one of many possible levels of resolution for looking at humanity. Taking what we might call the Gray’s Anatomy approach, we might treat all humans as the same, so when they get condition X they receive drug Y. But the facts of human variation make a nonsense of this approach, and we have the tools to take a more fine-grained approach to matching drugs with genetic profiles. At the other extreme, the finest resolution we could achieve would be the complete genome sequence of every individual along with knowledge of it varies from every other genome. This is currently unfeasible. But there are intermediate levels of resolution, and race seems to be one. Of course, it would be best to identify the genetic underpinnings of the differential response to BiDil among blacks and whites, and to then test heart failure patients for the presence of these genes, prescribing BiDil to only those with the ‘right’ combination. If this could be achieved, the efficacy of BiDil would increase even further in this tightly defined group. But in the meantime, the facts of ancestry mean that the increased statistical likelihood that black individuals will carry genes that enhance response to BiDil can be used to bring benefit to heart failure patients or at least one race.

It’s time to summarise the case for race. Races are genetically distinct groups: there aren’t such groups to even begin to correspond to standard racial classifications. However, “be used to distinguish human groups having a common heritage and to assign individuals to particular ones”; “Given that people can be sorted broadly into groups using genetic data, do common notions of race correspond to underlying genetic differences among populations? In some cases they do, but often they do not.”. And race has apparent worth in medicine, as the DiBil case demonstrates.

Now, if you can accept the above, and then go back to what Pinker wrote, and what Armand Leroi wrote (on Edge and in the NYT), then I think it will seem a lot more reasonable, a lot less racists, and something worthy of at least thinking – not rejecting out of hand – even if you end up disagreeing on some or all points.

Thinking about race
Whatever your take on all this is, race is clearly an emotive, hot-button topic, and views on race are susceptible to ideological influence in a number of ways. Indeed, Lewontin’s ideological commitments have long been highlighted as colouring his scientific view of the world (a compliment he has returned to his critics). I’ll lay my cards on the table and say that I think that Lewontin is unduly ideological in his writings, and his views on some scientific topics are more motivated by a sincerely held concern for social justice than scientific truth (maybe some would see this as a good compromise, but here I’m assessing a scientific argument free from ideological commitments – but I suppose some will be imputed to me anyway by association with the views above). Jonathan Marks, who was on in the panel on race linked to above, has responded to evolutionary psychology with “Boy, this shit ticks me off” (a sentiment that Lewontin would echo), and this suggests an attitude that would also want to reject the idea of race (I realise this isn’t an argument, more a sociological observation). Interestingly, Mixing Memory also doesn’t like evolutionary psychology, or Steve Pinker in particular. I suspect that the same sort of general outlook motivates both the rejection of ev. psych. and the idea of race (“Yes”, will be the response: “They’re both a load of rubbish!”).

Responding to criticisms of the notion of race doesn’t require this sort of line of enquiry, but I think it’s important to identify why people might be driven by perhaps non-scientific reasons to reject certain findings or ideas (Pinker’s The Blank Slate is an extended attempt at just such an exercise, and also serves as a corrective to some of the misplaced fears surrounding the idea of human nature and the ideas of ev. psych. in particular; I have to say that I think Pinker is spot on here, but again that doesn’t really have anything to do with whether the argument about race is good or not). As I say, I’m trying to understand why people are so keen to reject certain ideas, even those they perhaps do not understand very well.

In the case of Mixing Memory one doesn’t have to look far. An earlier post on MM was entitled ‘I’m a racist: one cognitive scientist’s thoughts on racism part 1’. I’m really not trying to take a cheap shot here by merely putting the title in – the post is not a proud announcement of racist views, but a soul-searching examination of the pernicious effects of growing up in a racist climate even when you explicitly reject the racism you are surrounded by. It’s all commendable stuff. But it does provide a clue as to why MM is so sensitive about issues of race.

I didn’t grow up in an overtly racist environment, attended a mixed school, had and have black and Asian friends (I’m not saying, “See, I couldn’t be racist!”, just pointing out that mixing with people of different ethnicities to me was and is common), and now happen to have a Chinese girlfriend (well, British born, but of Chinese ethnicity). I’m concerned about racism and racial attitudes, but am relaxed about my racial attitudes, in that I really don’t think I have any racial hang-ups or latent racism (I know this could all be self-serving delusion, but I have no evidence that I’m racists and plenty of clues that I’m not!). Perhaps if I was writing from the deep South 40 years ago I would much more sensitive to talking about race, and might want to be able to comfortably ignore the findings of race being produced by science (imagine the science of today was available then). But this doesn’t make the science wrong. As understandable as it is that you don’t want racial differences to be highlighted and magnified because of the potentially harmful uses to which such ideas can be put is not an argument against the validity of the science of race. In any case, the ideas discussed above don’t justify racism at all, and in fact, as Pinker points out, it’s a pretty weak idea of racial equality that depends of the fact of genetic similarity (see Crow on related points) – we shouldn’t treat people well because they share the same genes us as, but because they’re humans and are deserving of the same treatment as ourselves regardless of how similar or different they are from us. And it’s always wrong to treat an individual as if they were an abstract average of the group you or they decide they belong to (whether that be based on race, sex, sexuality and so on).

Perhaps when we’re being listened to by racists we might want to avoid using the phrase ‘racial differences’, but among reasonable people we should be able to discuss the science of race sensibly, without racist connotations, and such discussions might have important health consequences, as the BiDil story illustrates.

15 Comments:

Blogger Chris said...

Hey, this is a nice post. There's actually much in it with which I agree. For instance, I know that medical science can benefit from treating different groups differently (this goes not only for traditional "races," but even different cultural groups). However, with race at least, the benefits of doing so are very limited, usually to a few diseases. And with heart disease, for example, it's not clear how much of the benefit of treating African Americans as a separate group is due to cultural vs. genetic factors (though obviously, with sickle cell, it is genetic).

The question, though, is to what extent is race scientifically useful. If we exclude its limited usefulness in medicine, we're not left with much. As some of your quotes hint at, on many empirical measures, there is more intra-group variability than inter-group variability. In other words, while we may be able to distinguish people of African descent from people of Asian descent genetically, the differences are very small and we have to look very closely, while the differences in, say, behavioral measures (intelligence, agression, whatever) are much greater within the races than between them.

What I dislike about Pinker's discussion of the topic (along with the topic of gender differences in cognitive ability) is not so much that he's wrong, even if he is, but that he has no idea what he's talking about, so if he's right, it's largely by chance. On the issue of gender, he's ignorant of huge (and I mean huge) parts of the literature, and he hasn't displayed any knowledge of the literature on cognitive differences between races (and there's a pretty large literature, especially post-Bell Curve). If he were merely wrong, but not out of ignorance, I wouldn't react so harshly. Scientists disagree all the time, even when looking at the exact same data.

5:39 am GMT  
Blogger Simon said...

Another interesting post, thanks Dan. I have no preference for or against the notion of human races, but how would the supporters of that notion react to a phylogeny of human races?

12:06 pm GMT  
Blogger RPM said...

Most of the human genetic diversity is located in Africa. If you construct a genealogy, I'm pretty sure Europeans and East Asians come out as monophyletic groups (or, at least, pretty damn close). Africans, on the other hand, are a paraphyletic group (not a true clade) and make up the majority of the tree. If we would like to properly define race (in an evolutionary/common descent manner), then we would have Europeans, East Asians, Native Americans, some other groups, and a whole bunch of African races. African is not a race in the same way that European or East Asian is a race.

6:29 pm GMT  
Blogger Simon said...

RPM,

So I guess I asked a silly question. Indeed, I remember now that the diversity amongst the African populations is a molecular argument for or african origin... Doesn't that pretty much destroy the concept of human races in a phylogenetic sense, when it is actually based on such a small fraction of our 'epidermic phenotype'?

10:09 pm GMT  
Anonymous Anonymous said...

I think there is a bit of a beat-up on Pinker. His post was in the context of commenting on what type of ideas might be contentious, not intended as a full discourse on the subject. I find it hard to argue with this statement of his:

Group differences, when they exist, pertain to the average or variance of a statistical distribution, rather than to individual men and women. Political equality is a commitment to universal human rights, and to policies that treat people as individuals rather than representatives of groups

Philip

12:50 am GMT  
Blogger Dan Jones said...

Time to reply en masse.

Chris, glad you liked the post, and that it was mostly agreeable. I’m not sure whether the question is whether the concept of race is biologically useful (its use in the taxonomic literature suggest it has some use), or quite what you mean by that - do we mean whether we can do anything practically useful with it, or merely whether it increases our understanding of the world? I think it does OK on the latter score, if your concept of race is sufficiently subtle – it helps you realise how ancestry and geographical isolation are related to the genetic composition of populations, and to grasp the nature of human genetic diversity. Of course, to the extent that the concept is abused we should be careful how we talk about race, but we shouldn’t throw the baby out with the bathwater.

As for Pinker just being right by chance, how do you know? Pinker has certainly read much of the relevant literature, and his arguments echo those of other experts – the fact that he’s not a specialist in this area should not preclude him having a valid opinion of the topic. If he’s understood and internalised the arguments of experts, then when he uses them they’re as valid as when an expert uses them. I guess whereas I trust that he has read the literature (some at least – whose read it all?) and understands it and genuinely believes the arguments he puts forward to be scientifically valid, you’re more suspicious that he’s motivated to simply pick out those ideas that fit his worldview.

RPM/Simon: it seems right that the peoples we typically pick out as being East Asian are a monophyletic group, but with such racial divisions there might be clusters (defined genetically) that are more like races in the sense mentioned by Mary, and these might not be exactly the same as racial groups that we might define on the basis of superficial external traits (skin colour, hair texture and so on). But I don’t think it follows that the notion of human races in phylogenetic sense (I’m not too sure what this means actually) – the races defined by genetic clustering based on ancestry are compatible with the idea that the races we define as East Asian, European and so on are monophyletic (I think – someone correct me if this is wrong).

I think Philip is right that there is a bit of a tendency to beat up on Pinker (and evolutionary psychologists generally), but he’s a big boy and can probably look after himself. In any case, Pinker and other evolutionary psychologists have beat up on their critics (in my view with more justification), scientifically if not personally (although they have impugned the motives of their critics). Sometimes the heat generated by the exchanges distracts from any light that might have illuminated the topics, and this is lamentable (if, academically, understandable), but I think we can move past this era of intellectual baiting and talk about the issues constructively. At least I hope we can.

8:29 pm GMT  
Blogger Fido the Yak said...

If I believed Pinker meant to talk about human groups in way consistent with the groupings RPM points to, I would still say he is a racist, but I would be inclined to admit that the word could be taken in a less perjorative sense than is commonly understood.

I don't understand who's supposed to be a contrarian fringe expert in this discussion. Cavalli-Sforza's vita and list of publications is quite impressive to me, though he has not to my knowledge published in Daedalus, and I am myself a contrarian fringe dilletante. So a big grain of salt there.

It was a mistake, I now realize, to assume that people who read my blog and genuinely cared about the scientific description of human genetic diversity would be familiar, or have the ability and the gumption to make themselves familiar, with the American Antrhopological Association's Statement on "Race", and their Statement on "Race" and Intelligence, or the American Association of Physical Anthropologists' Statement on the Biological Aspects of Race.

"Pure races, in the sense of genetically homogenous populations, do not exist in the human species today, nor is there any evidence that they have ever existed in the past." Further, the AAPA states, "There is no necessary concordance between biological characteristics and culturally defined groups. On every continent, there are diverse populations that differ in language, economy, and culture. There is no national, religious, linguistic or cultural group or economic class that constitutes a race. However, human beings who speak the same language and share the same culture frequently select each other as mates, with the result that there is often some degree of correspondence between the distribution of physical traits on the one hand and that of linguistic and cultural traits on the other. But there is no causal linkage between these physical and behavioral traits, and therefore it is not justifiable to attribute cultural characteristics to genetic inheritance." That is the consensus opinion of scientists who specialize in the study of human physical diversity. I have no wish to imply that the weight of expert opinion refutes Pinker; I mean to state it flat out.

4:49 am GMT  
Blogger Luke said...

"Pure races, in the sense of genetically homogenous populations" are called clones.

BTW, as someone who grew up in the border South 50 years ago and returned decades later I can testify that overt, casual racism hardly exists in this part of the country anymore -- far less than in, say, NYC.

2:46 am GMT  
Anonymous Anonymous said...

That is the consensus opinion of scientists who specialize in the study of human physical diversity. I have no wish to imply that the weight of expert opinion refutes Pinker; I mean to state it flat out.

Ummmm...no.


1. MIT technology review article on the The Haplotype Map (mirrored on GNXP)

formed a $100 million, three-year plan to chart just such a map. It’s called the International HapMap Project, and beginning with several hundred blood samples collected from Nigeria, Japan, China, and the United States, it will use highly automated genomics tools to parse out the common haplotype patterns among a number of the world’s population groups … the HapMap, together with a series of powerful genomic tools developed over the last several years, will make it possible to spell out in great detail the genetic differences between peoples from different parts of the world. … Ultimately, all of genetics boils down to measuring the genetic variation in some population of people and comparing it to their characteristics and looking for correlations. That’s all genetics ever is.” And, adds Altshuler, the HapMap “is simply a tool to study genetic variation at unprecedented levels of accuracy and detail.” … They also found that how people categorized themselves—whether they called themselves black or white or Asian—correlated closely with the genetic categories. … Race, of course, already plays a huge role in how doctors diagnose and treat patients. Physicians are well acquainted with the idea that Caucasians with northern-European ancestry have higher rates of cystic fibrosis than Asians and blacks, while African Americans suffer from higher rates of hypertension and diabetes.

2. Yale’s ALFRED database:

ALFRED contains allele frequency data on polymorphic loci for different human populations. As genetic polymorphisms, the common alleles at these loci must be considered normal variations. While it is a demonstrable fact that different populations have different frequencies of these alleles, most of the common alleles are present in most human populations. Many studies have shown that for any one genetic polymorphism most of the variations will occur among the individuals within each population because of the different genotypes. Only a small additional proportion of the global variation occurs as gene frequency differences among populations. Those differences, however, can illuminate evolutionary histories of human populations and may be especially relevant to design and conduct of biomedical research.


3. The cover of Scientific American

Does Race Exist? If races are defined as genetically discrete groups, no. But researchers can use some genetic information to group individuals into clusters with medical relevance … scientists have collected data about the genetic constitution of populations around the world in an effort to probe the link between ancestry and patterns of disease … about 10 percent of the variation distinguishes continental populations … Some polymorphisms do occur in genes, however; these can contribute to individual variation in traits and to genetic diseases. As scientists have sequenced the human genome (the full set of nuclear DNA), they have also identified millions of polymorphisms. The distribution of these polymorphisms across populations reflects the history of those populations and the effects of natural selection. … The frequency of the FY*O allele, which corresponds to the absence of Fy antigen on red blood cells, is at or near fixation in most sub-Saharan African populations but is very rare outside Africa … By looking at the varying frequencies of these polymorphisms, they were able to distinguish five different groups of people whose ancestors were typically isolated by oceans, deserts or mountains: sub-Saharan Africans; Europeans and Asians west of the Himalayas; East Asians; inhabitants of New Guinea and Melanesia; and Native Americans. They were also able to identify subgroups within each region that usually corresponded with each member’s self-reported ethnicity. … West Africans generally have polymorphism frequencies that can be distinguished from those of Europeans, Asians and Native Americans … Several of the polymorphisms that differ in frequency from group to group have specific effects on health … In these examples—and others like them—a polymorphism has a relatively large effect in a given disease


4. Neil Risch’s Genome Biology article

Neil Risch of Stanford University, a leader in the field of genetics, contends that race is helpful for understanding ethnic differences in disease and responses to disease. His position was prompted by an editorial last year in the New England Journal of Medicine asserting that “’race’ is biologically meaningless,” and one in Nature Genetics warning of the “confusion and potential harmful effects of using ‘race’ as a variable in medical research.”
1. In large part, the controversy stems from advances in DNA research streaming from the Human Genome Project—and trying to reconcile the fact that the pattern of DNA data differs among ethnic groups.
2. All humans have the bulk of their genetic heritage in common and possess the same set of genes.
3. But because of mutations—or changes in DNA —each gene comes in slightly different versions, and some of them are more common in one ethnic group than another.
4. These genetic differences often have medical significance—since some occur among genes that affect susceptibility to disease and the response to drugs.
5. For example, a mutation that causes hemochromatosis, a disorder of iron metabolism, is rare or absent among Indians and Chinese, but occurs in 7.5 percent of Swedes. Differences involving susceptibility to sickle cell anemia and lactose intolerance have been noted among ethnic groups and races.
Risch points out that many studies have shown that these differences cluster into five major groups, which are simply the world’s major continental areas and the people who once bred in them in isolation—sub-Saharan Africans; Caucasians, including people from Europe, the Indian subcontinent and the Middle East; Asians; Pacific Islanders and native Americans


5. Cavalli Sforza’s Geography of Human Genes

These studies were soon extended to other blood-group systems, and a body of data began to accumulate showing that different human populations have different proportions of blood groups. However, the first glimpse of the staggering magnitude of genetic variation came later—beginning in the 1950s and coming to full development in the 1960s—when individual differences for proteins could be systematically studied. A protein is a large molecule made of a linear sequence of components called amino acids; different proteins vary considerably in their amino-acid composition and serve very different functions


6. Sally Satel’s NY Times op ed on the utility of race in medicine:


Not surprisingly, many human genetic variations tend to cluster by racial groups—that is, by people whose ancestors came from a particular geographic region. Skin color itself is not what is at issue—it’s the evolutionary history indicated by skin color. In Africa, for example, the genetic variant for sickle cell anemia cropped up at some point in the gene pool and was passed on to descendants; as a result, the disease is more common among blacks than whites. Similarly, Caucasians are far more likely to carry the gene mutations that cause multiple sclerosis and cystic fibrosis. Admittedly, race is a rough marker. A black American may have dark skin—but her genes may well be a complex mix of ancestors from West Africa, Europe and Asia. No serious scientist, in fact, believes that genetically pure populations exist. Yet an imprecise clue is better than no clue at all.


Point: whether you call them races or population groups, there is a pattern of genetic variation which correlates with geographic ancestry. Self-identification corresponds well to this underlying pattern of genetic variation. Skin color is only a noisy indicator of geographic ancestry; Indians and Mexicans may have similar skin colors, but they’ll have substantially different ancestries and allele frequencies – not to mention other morphological differences. The best way to think about races is as fuzzy clusters in a high dimensional marker-space. You can make this precise by downloading data sets from the aforementioned ALFRED (point 2 above) and plugging them into Matlab. Alternatively, you can look at Cavalli Sforza’s book (point 5 above) or the hapmap data. Upshot: geographically-correlated variation in human genetics is real. It has functional consequences. It has been implicated in all kinds of variation, both normal variation (e.g. in drug response) and disease-related. And we are spending millions of dollars and thousands of hours on mapping that variation more precisely than ever before.

2:55 am GMT  
Anonymous Anonymous said...

To be precise, it is this statement:

There is no necessary concordance between biological characteristics and culturally defined groups

Which is flatly false. Again from the references above:

By looking at the varying frequencies of these polymorphisms, they were able to distinguish five different groups of people whose ancestors were typically isolated by oceans, deserts or mountains: sub-Saharan Africans; Europeans and Asians west of the Himalayas; East Asians; inhabitants of New Guinea and Melanesia; and Native Americans. They were also able to identify subgroups within each region that usually corresponded with each member’s self-reported ethnicity.

Point: rather than calling for others to read the literature, perhaps you should educate yourself. Start googling the haplotype map and take it from there. If race (or population group variation, the nomenclature is secondary) wasn't biologically significant, why would we spend hundreds of millions of dollars sequencing the SNPs of 50 Nigerians, 50 Chinese & Japanese, and 50 Northwest Europeans?

Why not just sequence 150 Northwest Europeans?

3:00 am GMT  
Anonymous Anonymous said...

Excellent discussion. Many people are threatened at the possibility of racial and ethnic differences in important human characteristics. Many people will go to great lengths to deny the obvious. Regardless, the hapmap project will not be the last of its kind. There is simply too much to learn from this type of study.

5:12 am GMT  
Anonymous Stephen said...

The issue here is that this is dangerous terrirory. Although I agree with Pinker in The Blank Slate, we should not base how we treat people on their race, even if race turned out to really matter.

But I think Pinker is speaking from a nice bubble of science, where the world should be tolerant because it is. Yes we must study race. It is important science. But we must try to keep science out of politics. I think Pinker seriously misread the situation with the math gender differences. He saw people who were afraid to ask hard questions, when in reality it was just politics and science didn't enter into it.

The danger of studying race is that is becomes easily political. The wall must be high and thick between politics and science in this department.

12:33 am GMT  
Anonymous Anonymous said...

Does anyone know the the genetic distance between east asians (japanese, korean, chinese) and chimps? I have heard that Karachi mongoloids are pretty close to chimps in terms of genetics. At a site called EZ-board the claim is that nigerian genes closely resembel that of chimpanzees. Is there a bigger genetic difference between europeans and africans(eg. sokoto nigerians) than there is between east asians (japanese(koreans/chinese) and africans (eg. sokoto nigerians)? I have heard that in some old studies East asian are furthest away in terms of genetic distance from africans, but i have also heard that more recently studies (more comprehensive studies) puts the east asian like the japanese and koreans closer to the africans than europeans.

1:31 pm GMT  
Anonymous Anonymous said...

First,
Jewish people are the most intelligent. They win almost %40 of the Nobel Prize's and they have a small population of only 14 million. So by far they exceed the other races in intelligence. The other races having huge numbers and such small contributions.

Second,
IQ tests, test intellectual conformity, not creativity and originality. This would explain the Asian high IQ's. They as a people are the ultimate conformists.

In IQ tests there are typically only one answer to the problem. That problem being a social conformity to reason. But everyone knows that Genius's and all the greatest developments in the world are not the product of conformity. Conformity never breeds creativity. We can see this in the lack of influence the Asian population has had on Science. China used to be called the "sick man" of Asia. Their population is massive and their contribution to innovation is almost nil. We can see this lack of originality in their adoptation of European philosophies, I.e. Communism. As well in all of China's 2 Billion people there was no one who could design a car for their new car company so they hired Italians to do it. The Asian races remain as factory slaves for European and Western peoples.

Friedrich Nietzsche and other Philosophers have made fun of Asian people as a race. Nietsche used the words "Pallid osification" to describe Orientals.

Pallid: lacking sparkle or liveliness : dull

Osification: Process of becoming inflexible: the process of becoming set and inflexible in behavior, attitudes, and actions.

5. Inflexible conformity: rigid, unthinking acceptance of social conventions.

The reality is Asian people have yet to understand that laws and rules are arbitrary. Europeans make the rules and Asian's follow them.

It also doesn't make sense that Asian's are considered smart because of the fact that they have destroyed their own countries. This is due to over-population and their basic lack of enviromental understanding.

It is also common scientific fact that women who have many children are ignorant, and those who have less children are more intelligent. This has already been proven in studies. So it seems strange to say that Asians are smart when the obviousness of their backwards country, and medieval lifestyle makes them contrary to that premise.

Europeans have the most advanced civilizations and every other race has yet to meet these levels other than the Japanese. The Japanese only being good at copying other people's inventions and making them better. Other than that their original creativity is lacking as well. They took American cars and made them better. They took the German camera and made it better. And they took German steel and made it better. Otherwise the greatest advances still come from Europeans and Jews. Other than that the Orientals have yet to produce an Einstein or Thomas Edison. One Thomas Edison who created 2000 or so patents is probably heads and tails over 100 million orientals in mental originality.

When it comes to Black people. It makes sense that they have low intellectual comformity, I.e. IQ tests. They are far too creative to be trapped in this unoriginal form of conditioning. You can tell their creative capacity in their athletics, music, dance, and the way they talk. They by far exceed the Asiatic races in these areas. Being better singers, musicians ect. I have yet to see an Asian person talk out of the norm. The only type of originality they have is mimicry. Blacks far exceed Asians in emotive expression. In all of North America there is only one or two famous high-paid Asian actors.

Reality, europeans rule the world and they have allowed others to exist only out of desire for economic bennifet. They, (europeans) are also the physically strongest, winning the Strongest Man competitions again and again. And they have become the most effective hunters due to their neccesity for animal food stuffs in a northern climate with lack of vegetables. The progression of killing animal to foreign humans, being a small step when resources and land were diminishing due to increased population and cultural expansion.

The greater the conformity, the weaker the race. Thus we see the races as they are today. The wild animal being bred out of man, and the physically impotent, dull conformist thriving. The intelligent genius being alone and trampled by the herd.

Otherwise "group psychology" is the most destructive thing in the world. All these stereotypes are false when it comes to the individual. Individualism is the most important thing for this time. All countries, Relgions, groups need to dissolve for man to live in peace.

7:23 am GMT  
Blogger Anesha said...

Hi Nice Blog . I don't really know a lot about Human Anatomy study or art, but that's just my 2 cents. Really great job though, Krudman! Keep up the good work!

6:03 am GMT  

Post a Comment

Links to this post:

Create a Link

<< Home