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Science/Tech See other Science/Tech Articles Title: Genetic Reality of Race The Genetic Reality of Race In WHERE DO WE COME FROM: The Molecular Evidence for Human Descent (Springer, 2002) Klein and Takahata write, on page 381, ''The species, as the only biologically definable category, provides a dividing line in biological classification. Most of the other categories (genus, family, order, etc) are positioned above the species level, while only a few are in the sub-species level. The latter, which include variety, subspecies, and race, are poorly defined and ambiguous. Any deviation from the holotype, the specimen on which the description of a new species is based, is referred to as a variety, even when the deviation is in a single morphological character. A subspecies is a population or a group of phenotypically similar populations inhabiting a geographically defined region and differing from other populations of the same species in diagnostic characters. Race is used by taxonomists either as a synonymn of sub-species or as a designation of a local population within a sub-species. Different variants, subspecies, or races of the same species are either known or expected to interbreed if given the opportunity.’’ [Note that only a single character is enough to distinguish a 'variety', and SOME distinguishing designation is certainly called for between Europeans and Asians. Thus we can conservatively say Euros and Asians are different varieties. Next, consider that statement, ''race is used by taxonomists either as a synonym of sub-species or as a designation of a local population within a sub-species''. That means race signifies a greater distinction than variety, and it might be used to distinguish a 'lesser' difference than subspecies. Klein and Takahata discuss how the gorillas are divided into subspecies by their fur length and color or various morphological characteristics. They go on to say,] ''All this is biological reality which raises few emotions. Taxonomists may disagree on the number, delineation, name, indeed on the very existence of the subdivisions in a particular species, but other than that they find nothing objectionable about the notion of species consisting of populations between which gene flow has been reduced, because of the geographical distance between them, for example.'' and ''Biologically, H. sapiens is a species like any other and as such it might be expected to be differentiated into subspecies, especially since its global distribution creates opportunities for adaptation to different climatic conditions and so for morphological divergence.'' [Commenting on the current, PC effort to deny the very existence of race, K and T write,] ''The proposal to scrap the concept of race altogether is currently only one extreme in a range of views. It is certainly not shared by all anthropologists and is by no means the majority opinion of the public at large. It appears to be a conclusion reached more on the basis of political and philosophical creeds than on scientific arguments. Correspondingly, anthropologists who do hold this opinion often attempt to shout down their opponents rather than convince them by presentation of facts. Their favored method of argumentation is to label anybody who disagrees with them as racist. The public, however, seems unimpressed by their rhetoric. It refuses to believe that the differences they see are a mere figment of their imagination. A lay-person can tell with a high degree of accuracy where individuals come from just by glimpsing their features.” [The authors give a specific example and go on to write,] ''Except for some anthropologists, everybody else seems to be able to distinguish people from different parts of the world at a glance by their outward appearance. This apparently is also the view of some government administrators in countries with programs designed to fight racial discrimination. Obviously, there is a credibility gap between some anthropologists on the one side and the public, as well as the governments of some countries, on the other. One way to settle the arguments among anthropologists and to reconcile anthropologists with the public might be to move away from physical characteristics and focus on the genes. If races are real, they should have a genetic basis separable from environmental and cultural influences.'' and ''Provided the races separated a long time ago, random genetic drift should have diversified their genetic composition even in the absence of selection. It can be expected that the longer ago the races diverged, the greater the differences between them will be. Even if there has not been enough time to 'fix' different alleles in distinct races, at least differences in gene frequencies should have been generated.'' [The research discussed in Letter to the Editor of Discover (posted on site) describes the results from the sort of study Klein and Takahata suggest. It turns out there ARE fixed alleles that vary by race, and different frequencies that are associated with Africans, Europeans, and Asians. In other words, there ARE genetic 'races' in spite of the disingenuous statements that are publicized in an attempt to obfuscate and deny the facts. Everyone has noted that Europeans have white skins; many of them have lightly pigmented eyes and hair; on the other hand Africans have dark skin, hair, and eyes, while Asians have dark eyes and hair, and Eurasian hair has a different texture from that of Africans. Harding et al. (in Evidence for Variable Selective Pressure at MC1R, Amerian Journal of Human Genetics, 66:1351-61, 2000) studied the MC1R gene, which influences the pigmentation of eyes, hair, and skin. They found that all Africans, and tropical indigenes in general, had an ancestral form of the gene, as also found in chimps: there were NO non-synonymous alleles. Thus, they contend that MC1R is tightly constrained in the tropics; this implies that any population radiating 'Out of Africa' would have been black. By contrast, there were several alleles, at various frequencies among European populations, accounting for the observed ubiquity of white skin, and substantial frequency of light hair and eye colors. These alleles could ONLY have arisen in populations that left the tropics a very long time ago, or never lived there to begin with. It would have taken a long time for the mutations in these alleles to occur and then rise to the observed distribution. Harding et al. calculate that at least a hundred thousand years, and possibly more than twice that long, might be required for one of these alleles to reach its current frequency. I defy any population geneticist to produce a credible model of genetic mutation and diffusion that turns an all-black African population into an all-white European population in the 50 to 70 thousand years that current Out of Africa models permit! And remember that those same afrocentrists claim the African radiation replaced the indigenous Eurasians, rather than interbreeding with them, so they can’t postulate acquisition of MC1R alleles from archaic Europeans, followed by selection to achieve fixation of euro-genes; that would be more like absorption than replacement! Moreover, they must, but can’t, explain why the putative African radiation in Asia produced an entirely different variety and set of alleles. The afrocentrists appeal to selection, but Harding finds evidence that MC1R has NOT been selected at Euro-specific alleles, though it has been tightly CONSTRAINED to the ancestral form in the tropics. Klein and Takahata, writing of the various attempts to explain what kind of selection would make ALL Europeans white, or account for their eyes and hair, concede that,] “None of these explanations is fully satisfactory” and “Satisfactory explanations are also not available for hair color and texture, eye color, and other external differences between human races.” [Before the recent advances in genetics it was possible to contend that black Africans were somehow converted into Eurasians. Geneticists speak glibly of ''drift'' as if it were a serious theory for how ALL those putative black Africans turned white in Europe and yellow in Asia; and not just their skin color, but all the other soft tissue, cranial, and intellectual features. Everybody changed completely and there was no mix of people with different degrees and phenotypic expressions of afro-characters. What kind of a pseudo-science theory of population dynamics could yield an ALL white-characteristic Europe from blacks? There is an old saying that some ideas are so dumb only highly educated people can believe them. As noted above, no satisfactory explanations were forthcoming for such conversion, but the socio-political, PC 'virtue' of an African origins theory was irresistible to academia and media opinion makers. The early research on mtDNA was misinterpreted to support the ''African Eve'', or ''Out of Africa'' theories, by asserting that all human mtDNA came from an African woman. This assertion is maintained today, and it continues to be represented as 'proving' African replacement, even though the data does NOT justify such an assumption. See Plural Lineages in the Human mtDNA Genome (posted on site) for contraindications. Since the morphological, genetically mediated, differences between Europeans, Asians, and Africans are so obvious, those who wish to deny the biological reality of race are forced (against all common-sense) to argue that such differences are statistically trivial. Lewontin, for instance, argues that since ''only'' 15% of the variation in the human genome is completely correlated to race, that such differences are trivial. As noted in the closing paragraph of Letter to the Editor of DISCOVER, this is a deceitful argument. Klein and Takahata are quite PC on the subject of race, but they have too much scientific integrity to misrepresent the data as Feldman does; here is what they say,] ''Formally, these findings demonstrate, first, that the species is indeed subdivided into genetically definable groups of individuals and, second, that at least some of those groups correspond to those defined by anthropologists as races on the basis of physical characters.'' [Klein and Takahata note that, in spite of the genetic findings, many continue to argue that such distinctions are trivial. Then they write,] ''By contrast, Sewall Wright, who can hardly be taken for a dilettante in questions of population genetics, has stated emphatically that if differences of this magnitude were observed in any other species, the groups they distinguish would be called subspecies.” [So, while genetic research does support traditional and common-sense racial distinctions, it is even more consistent with a nuanced view that the major distinction is between the indigenes of New Guinea/Australia and sub-Saharan Africans versus Eurasians. The differences between Europeans and northern Asians are minor by comparison, so the old tri-racial distinction of white, yellow, and black, while not invalid, is not strictly accurate from a taxonomic perspective. Genetically, we should regard Europeans and northern Asians as varieties of H. s. sapiens; the sub-Saharan Africans and Australian/NG populations as subspecies, and the back-crossed hybrid indigenes of N. Africa and much of southern Asia as one or more races. Klein and Takahata write,] ''One can extend Wright’s argument even further. The more than two hundred species of haplochromine fishes in Lake Victoria differ from each other much less than the human races in their neutral genes, although they are presumably distinguished by genes that control differences in their external appearances. The same can be said about at least some of the currently recognized species of Darwin’s finches and about other examples of recent adaptive radiations. In all these cases, reproductively isolated groups are impossible to tell apart by the methods used to measure differences between the human races. Obviously human races are not reproductively isolated (interracial marriages are common and the progenies of such marriages are fully fertile) but the external differences between them are comparable to those between the cichlid fishes and Darwin's finches. Under these circumstances, to claim that the genetic differences between the human races are trivial is more a political statement than a scientific argument. Trivial by what criterion? How much difference would Lewontin and those who side with him consider non-trivial?'' [Actually Klein and Takahata understate human racial differences by calling them ''comparable'' to the finches and cichlids, because only an expert can tell those birds and fishes apart, while any ordinary person can tell another person’s race at a glance! K and T go on to write,] “By mixing science with politics, geneticists and anthropologists are committing the same infraction of which they are accusing other scientists, whom they themselves label as racists. Even worse, by dismissing genetic differences as insignificant, they play into the hands of genuine racists who can easily demolish this claim.” [These genetic differences between human races offer an important test of the Out of Africa theory, and it fails!] “Multiregionalists have no difficulty explaining the 10-15% differences between the human groups. Since they assume that the differentiation began up to 2 my ago, when H. erectus established founding populations in the different regions, there has been sufficient time to accumulate the differences. Uniregionalists [Out of Africa theorists] who assume that the differentiation into groups began after the exodus of H. sapiens from Africa, are at a disadvantage, because calculations indicate that only under highly unrealistic assumptions (e.g., no gene flow between populations) would the time interval suffice for the origin of the observed differences.” Here is some research that gives a perspective on the claims that differences between human races are genetically insignificant. In Number of ancestral human species: a molecular perspective D. CURNOE*, and A. THORNE, (in HOMO Vol. 53/3, pp. 201-224) write: “Nuclear DNA Our analyses using 24 genetic distances provide an estimated speciation rate of 1-13 with a mean of 4 for all DNA distances (table 1). Some of the speciation rates in table 1 are <1. This results from the fact that some of the distances between humans and chimpanzees, when halved, are below those between Africans and Asians.” Just think about that: some of the genetic differences between Africans and Eurasians, are more than half as great as between the consensus human genome and chimpanzees! Compare the research cited above, in regard to the great difference between African and Eurasian nuclear and mtDNA, to the deceptive statements by Feldman, as quoted in Discover magazine (IMO…, posted on site). Next, consider how ‘racial’ differences, between Eurasians and sub-Saharan Africans, compare to the difference between modern humans and pre-human species of Homo. “We estimate the mean distance between H. sapiens and «terminal» H. neanderthalensis from 16 distances to be around 0.08%. This is a very small distance and is less than half the estimated genetic difference between living sub-Saharan Africans and Eurasians (Starr & McMillan 2001). The mean of 8 genetic distances between H. sapiens and H. neanderthalensis is 0.026-0.027. This is equivalent to the genetic distance between Papua New Guineans and Thais or Na Dene and Indonesians (Cavalli-Sforza et al 1994).” So, the difference between the modern human consensus genome, and H. neanderthalensis, is less than half the difference between s-S Africans and Eurasians. These are the differences: twice as much as the gulf between Hss and Hn, which Lewontin and the race-deniers call ‘trivial’! What about the genetic distance to H. erectus? “Homo sapiens and … H. erectus living about 0.3 Ma, … may have shared an ancestor around 1.5 Ma (a total divergence time of 2.4 million years). The distance between them as determined from the mean of 16 distances may have been around 0.19%. This is about equivalent to the estimated genetic difference between living sub-Saharan Africans and Eurasians of 0.2% (Starr & McMillan 2001). The mean of 8 other genetic distances between H. sapiens and H. erectus is 0.065-0.068. This overlaps the range of distances for living humans, with the lower estimate identical to the distance between «Bantu» and «Eskimo» (Cavalli-Sforza et al 1994).” So, modern Eurasians and s-S Africans are about as genetically distant as modern humans are from H. erectus! The authors say erectus and modern humans may have shared a last common ancestor about 1.5 million years ago. Notice how that fits with the data on fossil mtDNA included on chromosome 11 (see Australian Ancestry) which also implies that African erectus and Eurasians had diverged for more than a million years, before [on my view] hybridization between Eurasian sapiens and tropical erectus produced the indigenous populations of Africa and southern Asia. Even authors who have, in the past, minimized the importance of racial genetic distinctions are now admitting that the shibboleths, ‘race is a social construct’ and ‘we are all the same genetically’, are just plain wrong. As one reviewer wrote, “New support for the existence and significance of group, or racial, differences in medicine comes from several contributors to the [then] current Nature Genetics, a leading journal of genetics. This already widely noted issue is devoted to the question of whether inherited differences between groups should be considered in medical research and treatment, and though various authors deny the relevance of such differences, Sarah Tishkoff (University of Maryland) and Kenneth Kidd, of Yale, in “Implications of biogeography of human populations for race and medicine” report that racial differences indeed exist, while Joanna L. Mountain and Neil Risch, both of Stanford, in “Assessing genetic contributions to phenotypic differences among ‘racial’ and ‘ethnic’ groups,” recognize racial disparities and regard them as important for medical treatment.” The reviewer comments that, “The careful (and sometimes cautious) findings of these scholars may seem all too obvious, but they are an important corrective, in an authoritative source, to efforts to use such recent advances in genetic knowledge as the Genome to obscure the fact and the importance of racial differences.” The reviewer continues, writing of a recent Stanford study that … “…found a very close correlation between individuals' racial self-identification and the evidence from their DNA. In Genetic Structure, Self-Identified Race/Ethnicity, and Confounding in Case-Control Association Studies, which appears in the February 2005 issue of the American Journal of Human Genetics, a dozen researchers report the way the 3,636 individuals studied classified themselves racially tallied almost perfectly with their racial type as indicated by 326 signposts in their DNA: only 5 participants volunteered a racial identity at variance with that indicated by their genetic material. Intriguingly, the study also determined that the DNA of self-identified African-American and Hispanic participants, despite their substantial genetic admixture from other racial groups (and despite their historical tendencies to identify with other racial groups), jibed with their expressed racial membership as often as did those of whites and East Asians. The largest of its kind to date, the Stanford study focused on four major racial groupings (white, East Asian, African-American, and Hispanic) and was conducted in fifteen locations in the United States and Taiwan. Study leader Neil Risch, currently a professor at the University of California at San Francisco, believes that the demonstrated ability of prospective patients to accurately specify their group DNA can save time and money otherwise spent on painstaking individual genetic testing. … Without knowing how the participants had identified themselves, Risch and his team ran the results through a computer program that grouped individuals according to patterns of the 326 signposts. This analysis could have resulted in any number of different clusters, but only four clear groups turned up. And in each case the individuals within those clusters all fell within the same self-identified racial group.” Risch said, “people’s self-identified race is a nearly perfect indicator of their genetic background, contradicting the race-as-social-construct view”. I commend those authors for having the courage to tell even a little of the truth about this PC-censored topic. A paper by Deka, et al., titled: Population genetics of dinucleotide (dC-dA)n.(dG-dT)n polymorphisms in world populations (Am J Hum Genet. 1995 Feb;56(2):461-74) is both pertinent and long-ignored. “We have characterized eight dinucleotide (dC-dA)n.(dG-dT)n repeat loci located on human chromosome 13q in eight human populations and in a sample of chimpanzees. Even though there is substantial variation in allele frequencie at each locus, at a given locus the most frequent alleles are shared by all human populations. … The microsatellite loci examined here are present and, with the exception of the locus D13S197, are polymorphic in the chimpanzees, showing an overlapping distribution of allele sizes with those observed in human populations.” This study compares the genetic distances of eight human populations (Samoans, North Amerindians, South Amerindians, New Guineans, Kachari [Mongolids], Germans, more generalized Caucasians, and Sokoto: sub-Saharan Africans from Nigeria) to each other and to chimpanzees. The data were analyzed two ways - with Nei's standard genetic distance, and with modified Cavalli-Sforza distance. Using Nei's method, the Nigerian-chimp distance was 1.334 +/- 0.375, by far the closest value. By the Cavalli-Sforza method, the Sokoto Nigerians were again the closest to chimps (0.539) by a large margin. The farthest were again the South Amerindians (0.712), with the Germans (0.680) and general Caucasians (0.667) being a very close third and fourth behind the South Amerindians as well as Samoans (0.711) and North Amerindians (0.697). So, while the two methods give slightly different orders, in both cases the Nigerians are by far the closest group to the chimps. Once again, given the first method, these sub-Saharan Africans were at 1.334 while all the other groups ranged from 1.527-1.901, and given the second method they were at 0.539 while the other groups ranged from 0.643 (Kachari again) to 0.712. Finally, there have been numerous publications asserting that modern humans are 99.9% genetically identical. EVEN if that were true, there are so many loci in the human genome that a tenth of a percent of them would be MILLIONS! As one of the authors (quoted below) observes, “that could explain differences” … NO doubt! However, that 99.9 figure is WRONG. As posted September 8th, 2004, in World Science: “New research casts doubt on the widely accepted belief that humans are 99.9 percent genetically identical. That statement has been used to argue that race isn't real. But two new studies suggest that percentage is too high, researchers say … “The 99.9 percent number is pure nonsense,” wrote Michael Wigler, of Cold Spring Harbor Laboratory, New York, in a recent e-mail. “I will not say anything more about it.” … Wigler is a co-author of one of the two studies, which is published in the July 23 advance online edition of the prestigious research journal Science. In it, the researchers wrote that they were surprised to find large-scale differences in human DNA. “There is considerable structural variation in the human genome [genetic code], most of which was not previously apparent,” they wrote. Wigler’s group sampled DNA from 20 people from around the world. They detected 76 major differences among the people, differences known as copy number polymorphisms. This means that some sections of genetic code are repeated, but the numbers of repetitions vary among people. This “could explain why people are different” … said Scherer, whose team reached similar findings to those of the Cold Spring Harbor group. “At first we were astonished and didn't believe our results because for years we had been taught that most variation in DNA was limited to very small changes,” Scherer said. But later he learned Harvard University researchers were making similar observations, so the groups combined their data and reached the same conclusion. The Cold Spring Harbor team found that these changes affected the code for 70 genes [just in the small set studied]. These included genes involved in Cohen syndrome - a form of mental retardation - as well as brain development, leukemia, drug resistant forms of breast cancer, regulation of eating and body weight. That [99.9%] figure has become one of the most prominent pieces of their [“race-isn't real” proponents] argument since about four years ago, when the number came from scientists associated with the Human Genome Project, a 13-year program to map the human genetic code. Lander - a researcher who has been quoted in published reports giving the 99.9 percent figure, and who works with the Whitehead Institute in Boston - didn’t respond to phone calls and e-mails requesting comment for this story. His secretary said he was abroad. Also unreachable was Craig Venter, chairman of the Institute for Genomics Research in Rockville, Md., U.S.A. He was president of a company whose research produced the 99.9 percent figure in 2001, Celera Genomics. He didn't return phone calls or repeated emails. .Miami University’s Jon Entine, author of, “Taboo: Why Black Athletes Dominate Sports and Why We’re Afraid to Talk About It,” wrote, in an e-mail: “Rats are about 95 percent the genetic equivalent of humans. These are ridiculous statements, although technically accurate. The use of the 99.9 percent figure by the popular press and scientists is, frankly scandalous.” [I agree.]
Poster Comment: There's no getting this genie back in the bottle.
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#1. To: Tauzero (#0)
It's about time, too. Sooner or later, and I hope it's sooner, the race deniers will lose their influence. Speaking of race, I have noticed, as have professional researchers, than when whites and blacks live together, the whites tend to live in the hills and the blacks tend to live in the valleys, where it's warmer. This has been noticed all over the world. I guess this is why there are "Scottish Highlanders," but no "African Highlanders." Go to someplace like the Ozarks, which is the best kept secret in the U.S, and it's almost 100 percent white. The Ozarks are also a worn-down mountain range, and fairly high in attitude. Everytime I visit it feels like home to me. I was raised in the Mississipi River Valley, right near St. Louis, and it has never felt like home. Way too hot and humid.
"We become what we behold. We shape our tools and thereafter our tools shape us." -- Marshall McLuhan, after Alexander Pope and William Blake.
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