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Post by Admin on Dec 10, 2021 19:11:28 GMT
More than 100 years ago, American sociologist W.E.B. Du Bois was concerned that race was being used as a biological explanation for what he understood to be social and cultural differences between different populations of people. He spoke out against the idea of "white" and "black" as discrete groups, claiming that these distinctions ignored the scope of human diversity. Science would favor Du Bois. Today, the mainstream belief among scientists is that race is a social construct without biological meaning. And yet, you might still open a study on genetics in a major scientific journal and find categories like "white" and "black" being used as biological variables. In an article published in the journal Science, four scholars say racial categories are weak proxies for genetic diversity and need to be phased out. They've called on the U.S. National Academies of Sciences, Engineering and Medicine to put together a panel of experts across the biological and social sciences to come up with ways for researchers to shift away from the racial concept in genetics research. "It's a concept we think is too crude to provide useful information, it's a concept that has social meaning that interferes in the scientific understanding of human genetic diversity and it's a concept that we are not the first to call upon moving away from," said Michael Yudell, a professor of public health at Drexel University in Philadelphia. Yudell said that modern genetics research is operating in a paradox, which is that race is understood to be a useful tool to elucidate human genetic diversity, but on the other hand, race is also understood to be a poorly defined marker of that diversity and an imprecise proxy for the relationship between ancestry and genetics. "Essentially, I could not agree more with the authors," said Svante Pääbo, a biologist and director of the Max Planck Institute for Evolutionary Anthropology in Germany, who worked on the Neanderthal genome but was not involved with the new paper. "What the study of complete genomes from different parts of the world has shown is that even between Africa and Europe, for example, there is not a single absolute genetic difference, meaning no single variant where all Africans have one variant and all Europeans another one, even when recent migration is disregarded," Pääbo told Live Science. "It is all a question of differences in how frequent different variants are on different continents and in different regions." In one example that demonstrated genetic differences were not fixed along racial lines, the full genomes of James Watson and Craig Venter, two famous American scientists of European ancestry, were compared to that of a Korean scientist, Seong-Jin Kim. It turned out that Watson (who, ironically, became ostracized in the scientific community after making racist remarks) and Venter shared fewer variations in their genetic sequences than they each shared with Kim. Assumptions about genetic differences between people of different races have had obvious social and historical repercussions, and they still threaten to fuel racist beliefs. That was apparent two years ago, when several scientists bristled at the inclusion of their research in Nicholas Wade's controversial book, "A Troublesome Inheritance" (Penguin Press, 2014), which proposed that genetic selection has given rise to distinct behaviors among different populations. In a letter to The New York Times, five researchers wrote that "Wade juxtaposes an incomplete and inaccurate account of our research on human genetic differences with speculation that recent natural selection has led to worldwide differences in IQ test results, political institutions and economic development." The authors of the Science article noted that racial assumptions could also be particularly dangerous in a medical setting. "If you make clinical predictions based on somebody's race, you're going to be wrong a good chunk of the time," Yudell told Live Science. In the paper, he and his colleagues used the example of cystic fibrosis, which is underdiagnosed in people of African ancestry because it is thought of as a "white" disease. Mindy Fullilove, a psychiatrist at Columbia University, thinks the changes proposed in the Science article are "badly needed." Fullilove noted that by some laws in the United States, people with one black ancestor of 32 might be called "black," but their 31 other ancestors are also important in influencing their health. "This is a cogent and important call for us to shift our work," Fullilove said. "It will have an enormous influence. And it will make for better science." So what other variables could be used if the racial concept is thrown out? Pääbo said geography might be a better substitute in regions such as Europe to define "populations" from a genetic perspective. However, he added that, in North America, where the majority of the population has come from different parts of the world during the past 300 years, distinctions like "African Americans" or "European Americans" might still work as a proxy to suggest where a person's major ancestry originated. Yudell also said scientists need to get more specific with their language, perhaps using terms like "ancestry" or "population" that might more precisely reflect the relationship between humans and their genes, on both the individual and population level. The researchers also acknowledged that there are a few areas where race as a construct might still be useful in scientific research: as a political and social, but not biological, variable. "While we argue phasing out racial terminology in the biological sciences, we also acknowledge that using race as a political or social category to study racism, although filled with lots of challenges, remains necessary given our need to understand how structural inequities and discrimination produce health disparities between groups," Yudell said.
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Post by Admin on Dec 10, 2021 22:12:15 GMT
Taking race out of human genetics Engaging a century-long debate about the role of race in science
By Michael Yudell,1* Dorothy Roberts,2 Rob DeSalle,3 Sarah Tishkoff2
In the wake of the sequencing of the human genome in the early 2000s, genome pioneers and social scientists alike called for an end to the use of race as a variable in genetic research (1, 2). Unfortunately, by some measures, the use of race as a biological category has increased in the postgenomic age (3). Although inconsistent definition and use has been a chief problem with the race concept, it has historically been used as a taxonomic categorization based on common hereditary traits (such as skin color) to elucidate the relationship between our ancestry and our genes. We believe the use of biological concepts of race in human genetic research— so disputed and so mired in confusion—is problematic at best and harmful at worst. It is time for biologists to find a better way. Racial research has a long and controversial history. At the turn of the 20th century, sociologist and civil rights leader W. E. B. Du Bois was the first to synthesize natural and social scientific research to conclude that the concept of race was not a scientific category. Contrary to the then-dominant view, Du Bois maintained that health disparities between blacks and whites stemmed from social, not biological, inequality (4). Evolutionary geneticist Theodosius Dobzhansky, whose work helped reimagine the race concept in the 1930s at the outset of the evolutionary synthesis, wrestled with many of the same problems modern biologists face when studying human populations—for example, how to define and sample populations and genes (5). For much of his career, Dobzhansky brushed aside criticism of the race concept, arguing that the problem with race was not its scientific use, but its nonscientific misuse. Over time, he grew disillusioned, concerned that scientific study of human diversity had “floundered in confusion and misunderstanding” (6). His transformation from defender to detractor of the race concept in biology still resonates. Today, scientists continue to draw wildly different conclusions on the utility of the race concept in biological research. Some have argued that relevant genetic information can be seen at the racial level (7) and that race is the best proxy we have for examining human g enetic diversity (8, 9). Others have concluded that race is neither a relevant nor accurate way to understand or map human genetic diversity (10, 11). Still others have argued that race-based predictions in clinical settings, because of the heterogeneous nature of racial groups, are of questionable use (12), particularly as the prevalence of admixture increases across populations. Several meetings and journal articles have called attention to a host of issues, which include (i) a proposed shift to “focus on racism (i.e., social relations) rather than race (i.e., supposed innate biologic predisposition) in the interpretation of racial/ ethnic ‘effects’” (13); (ii) a failure of scientists to distinguish between self-identified racial categories and assigned or assumed racial categories (14); and (iii) concern over “the haphazard use and reporting of racial/ ethnic variables in genetic research” (15) and a need to justify use of racial categories relative to the research questions asked and methods used (6). Several academic journals have taken up this last concern and, with mixed success, have issued guidelines for use of race in research they publish (16). Despite these concerns, there have been no
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Post by Admin on Dec 10, 2021 23:20:24 GMT
systematic attempts to address these issues and the situation has worsened with the rise of large-scale genetic surveys that use race as a tool to stratify these data (17). It is important to distinguish ancestry from a taxonomic notion such as race. Ancestry is a process-based concept, a statement about an individual’s relationship to other individuals in their genealogical history; thus, it is a very personal understanding of one’s genomic heritage. Race, on the other hand, is a pattern-based concept that has led scientists and laypersons alike to draw conclusions about hierarchical organization of humans, which connect an individual to a larger preconceived geographically circumscribed or socially constructed group. Unlike earlier disagreements concerning race and biology, today’s discussions generally lack clear ideological and political antipodes of “racist” and “nonracist.” Most contemporary discussions about race among scientists concern examination of population-level differences between groups, with the goal of understanding human evolutionary history, characterizing the frequency of traits within and between populations, and using an individual’s self-identified ancestry to identify genetic risk factors of disease and to help determine the best course of medical treatments (6). If this is what race in contemporary scientific and medical practice is about, then why should we be concerned? One reason is that phylogenetic and population genetic methods do not support a priori classifications of race, as expected for an interbreeding species like Homo sapiens (11, 18). As a result, racial assumptions are not the biological guideposts some believe them to be, as commonly defined racial groups are genetically heterogeneous and lack clear-cut genetic boundaries (10, 11). For example, hemoglobinopathies can be misdiagnosed because of the identification of sickle-cell as a “Black” disease and thalassemia as a “Mediterranean” disease (10). Cystic fibrosis is underdiagnosed in populations of African ancestry, because it is thought of as a “White” disease (19). Popular misinterpretations of the use of race in genetics also continue to fuel racist beliefs, so much so that, in 2014, a group of leading human population geneticists publicly refuted claims about the genetic basis of social differences between races (20). Finally, the use of the race concept in genetics, an issue that has vexed natural and social scientists for more than a century, will not be obviated by new technologies. Although the low cost of next-generation sequencing has facilitated efforts to sequence hundreds of thousands of individuals, adding whole-genome sequences does not negate the fact that racial classifications do not make sense in terms of genetics. More than five decades after Dobzhansky called on biologists to develop better methods for investigating human genetic diversity (21), biology remains stuck in a paradox that reflects Dobzhanky’s own struggle with the race concept: both believing race to be a tool to elucidate human genetic diversity and believing that race is a poorly defined marker of that diversity and an imprecise proxy for the relation between ancestry and genetics. In an attempt to resolve this paradox and to improve study of human genetic diversity, we propose the following.
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Post by Admin on Dec 11, 2021 2:11:05 GMT
Scientific journals and professional societies should encourage use of terms like “ancestry” or “population” to describe human groupings in genetic studies and should require authors to clearly define how they are using such variables. It is preferable to refer to geographic ancestry, culture, socioeconomic status, and language, among other variables, depending on the questions being addressed, to untangle the complicated relationship between humans, their evolutionary history, and their health. Some have shown that substituting such terms for race changes nothing if the underlying racial thinking stays the same (22, 23). But language matters, and the scientific language of race has a considerable influence on how the public (which includes scientists) understands human diversity (24). We are not the first to call for change on this subject. But, to date, calls to rationalize the use of concepts in the study of human genetic diversity, particularly race, have been implemented only in a piecemeal and inconsistent fashion, which perpetuates ambiguity of the concept and makes sustained change unfeasible (16). Having journals rationalize the use of classificatory terminology in studying human genetic diversity would force scientists to clarify their use and would allow researchers to understand and interpret data across studies. It would help avoid confusing, inconsistent, and contradictory usage of such terms. Phasing out racial terminology in biological sciences would send an important message to scientists and the public alike: Historical racial categories that are treated as natural and infused with notions of superiority and inferiority have no place in biology. We acknowledge that using race as a political or social category to study racism and its biological effects, although fraught with challenges, remains necessary. Such research is important to understand how structural inequities and discrimination produce health disparities in socioculturally defined groups. The U.S. National Academies of Sciences, Engineering, and Medicine should convene a panel of experts from biological sciences, social sciences, and humanities to recommend ways for research into human biological diversity to move past the use of race as a tool for classification in both laboratory and clinical research. Such an effort would bring stakeholders together for a simple goal: to improve the scientific study of human difference and commonality. The committee would be charged with examining current and historical usage of the race concept and ways current and future technology may improve the study of human genetic diversity; thus, they could take up Dobzhansky’s challenge that “the problem that now faces the science of man [sic] is how to devise better methods for further observations that will give more meaningful results” (21). Regardless of where one stands on this issue, this is an opportunity to strengthen research by thinking more carefully about human genetic diversity. ■
REFERENCES AND NOTES 1. F. Collins, Nat. Genet. 36 (suppl.), S13 (2004). 2. M. W. Foster, R. R. Sharp, Nat. Rev. Genet. 5, 790 (2004). 3. P. A. Chow-White, S. E. Green Jr., Int. J. Commun. 7, 556 (2013). 4. W. E. B. Du Bois, The Health and Physique of the Negro American (Publ. no. 11, Atlanta Univ. Publications, Atlanta, GA, 1906). 5. T. Dobzhansky, Genetics and the Origin of Species (Columbia Univ. Press, New York, 1937). 6. M. Yudell, Race Unmasked: Biology and Race in the 20th Century (Columbia Univ. Press, New York, 2014). 7. E. G. Burchard et al., N. Engl. J. Med. 348, 1170 (2003). 8. Y. Banda et al., Genetics 200, 1285 (2015). 9. C. E. Powe et al., N. Engl. J. Med. 369, 1991 (2013). 10. D. Roberts, Fatal Invention: How Science, Politics, and Big Business Re-Create Race in the Twenty-First Century (The New Press, New York, 2012). 11. D. Serre, S. Pääbo, Genome Res.14, 1679 (2004). 12. P. C. Ng, Q. Zhao, S. Levy, R. L. Strausberg, J. C. Venter, Clin. Pharmacol. Ther. 84, 306 (2008). 13. J. S. Kaufman, R. S. Cooper, Am. J. Epidemiol. 154, 291 (2001). 14. T. R. Rebbeck, P. Sankar, Cancer Epidemiol. Prev.14, 2467 (2005). 15. L. M. Hunt, M. S. Megyesi, J. Med. Ethics 34, 495 (2008). 16. A. Smart, R. Tutton, P. Martin, G. T. H. Ellison, R. Ashcroft, Soc. Stud. Sci. 38, 407 (2008). 17. G. Lettre et al., PLOS Genet. 7, e1001300 (2011). 18. K. Bremer, H. E. Wanntorp, Syst. Biol. 28, 624 (1979). 19. C. Stewart, M. S. Pepper, Genet. Med. (2015). 20. G. Coop et al., New York Times, 8 August 2014, p. BR6. 21. T. Dobzhansky, Mankind Evolving: The Evolution of the Human Species (Yale Univ. Press, New Haven, CT, 1962). 22. S. M. Fullerton, J. H. Yu, J. Crouch, K. Fryer-Edwards, W. Burke, Hum. Genet.127, 563 (2010). 23. L. Braun, E. Hammonds, Soc. Sci. Med. 67, 1580 (2008). 24. W. C. Byrd, M. W. Hughey, Ann. Am. Acad. Pol. Soc. Sci. 661, 1 (2015).
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Post by Admin on Jan 11, 2022 18:13:55 GMT
In a recent op-ed in The New York Times, “How Genetics is Changing Our Understanding of Race,” the geneticist David Reich challenged what he called an “orthodoxy” in genetics. Due to concerns of political correctness, he argued, scientists are unwilling to do research on—or, in some cases, even discuss—genetic variation between human populations, despite the fact that genetic variations do exist. “It is simply no longer possible to ignore average genetic differences among ‘races,’” he wrote.
The piece was widely circulated, drawing condemnation from some social scientists who were appalled by its implications and praise from people who believe that discussion of racial differences has become taboo. Predictably, it rang the bell for another round of an ongoing media fight over why there’s a gap between black and white IQ scores. Ezra Klein referenced the piece in Vox, and debated it with Sam Harris. Andrew Sullivan riffed on campus leftists and culture war.
At a time in America when white supremacists openly march in cities, perhaps it’s inevitable that any writing invoking notions of genetic variation is going to stoke fiery political debate. But for all the turmoil surrounding Reich’s op-ed, the actual science in it is remarkably uncontroversial. Reich describes race’s complex relationship to ancestry in a way that geneticists—myself included—widely agree upon. Where the op-ed gets into trouble speaks to a broader danger in genetics, one that makes the field particularly susceptible to being exploited for political and pseudoscientific ends: poor communication.
Race is a concept defined by society, not by genes. It’s true that people around the world differ genetically due to their ancestry, and that people’s racial identity may be statistically correlated with their ancestry, albeit unreliably. But “race” does not mean “ancestry,” and it’s a loaded term for scientific outreach: Biological races are not a current scientific concept and often reinforce historical biases.
In his op-ed, Reich explicitly acknowledges that race is a social construct. At several places in the text, he goes to great pains to distance himself from racism, and to point out that traditional ideas of race are contradicted by genomic data (including his own work). For instance, he notes that the ways different people and societies think about race are inconsistent:
In the United States, historically, a person is “black” if he has any sub-Saharan African ancestry; in Brazil, a person is not “black” if he is known to have any European ancestry. If “black” refers to different people in different contexts, how can there be any genetic basis to it?
Reich goes on to point out that how Americans racially categorize themselves correlates only weakly with genetics. There are complex social reasons for this, including a historical legacy of race-purity laws based on pseudoscientific ideas (for example, the one-drop rule, which classified Americans as black if they had even a single black ancestor). And so, for example, some Americans now identify as black due to a single grandparent from sub-Saharan African ancestry, or an equivalent proportion of their DNA. A 2015 analysis of 23andMe data, co-authored by Reich, found that around one in 10 self-identified African Americans have less than 50 percent of their genome attributable to African ancestry, and around one in 50 have less than 2 percent. The probability that someone of a given ancestry will report as a particular identity varies with, among other things, their age, their gender, and the number of other people of that identity who live nearby.
DNA evidence from ancient remains undermines any notion that racial categorizations—or even phrases like “African ancestry”—represent descent from some Platonic ideal of ancestral populations. Human populations appear to have repeatedly split, merged, and interbred. As Reich writes:
My laboratory discovered in 2016, based on our sequencing of ancient human genomes, that “whites” are not derived from a population that existed from time immemorial, as some people believe. Instead, “whites” represent a mixture of four ancient populations that lived 10,000 years ago and were each as different from one another as Europeans and East Asians are today.
One of the reasons race is not a firm concept for geneticists is due to this mixing process, which geneticists call admixture. Bursts of migration and interbreeding have recurred throughout human evolution. Your genome is a fine mosaic of your ancestors’—and you have a lot of ancestors.
All of this is textbook genetics—as Reich clearly knows, seeing as he did some of the research that demonstrated these claims. But his op-ed starts losing clarity when, thanks to some unfortunate language, the distinct concepts of “races” and “populations” seem to become admixed themselves. As an example, in discussing his lab’s use of self-reported race in tracking down genetic risk factors for prostate cancer, Reich places socially constructed terms (like “African-American”) right alongside the results of statistical inferences about genome history (such as “probably West African in origin”). He’s apparently trying to defend the use of both, but in the process somewhat blurs his earlier distinctions between race and ancestry.
Then there’s that passage I mentioned above in which he uses the word “races” in quotes:
I have deep sympathy for the concern that genetic discoveries could be misused to justify racism. But as a geneticist I also know that it is simply no longer possible to ignore average genetic differences among “races.”
The quotes around “races” are ironic. They’re there to subvert the apparent precision of the word, acknowledging—or at least trying to acknowledge—that many non-scientists nevertheless have some intuition that their perception of race can, loosely speaking, line up with guesses about ancestry. The root of Reich’s concern seems to be that if geneticists simply dismiss that intuition, we’ll lose credibility, as larger-scale genetic studies reveal increasingly subtle correlations between ancestry and human-trait variation. (Notably, in his new book, Who We Are and How We Got Here, from which much of the op-ed is drawn, the analogous sentence doesn’t use the word “races” at all: Reich instead uses “populations.”)
Readers can easily miss all this, especially if Reich’s words are excerpted or twisted to another author’s own ends. The science writer Nicholas Wade, whose writing on race has been widely panned by geneticists, brushed away the flimsy shield of ironic punctuation in a response to Reich in the Times: “At last! A Harvard geneticist, David Reich, admits that there are genetic differences between human races, even though he puts the word race in quotation marks.” In New York magazine, Andrew Sullivan talked quite un-ironically of “differences between the races.”
Reich’s op-ed includes not just vague words, but vague rhetorical logic. It seems to be creating a false balance between, on the one hand, some specifically named people who have expressed what Reich refers to as “insidious” views on race (such as Wade and James Watson, a co-discoverer of the structure of DNA ) and, on the other hand, “well-meaning people” who, according to Reich, are perpetuating some kind of “orthodoxy” that resists research on genetic variation. This argument, fleshed out with examples in Reich’s book, is that truculent and overly PC anthropologists, unobstructed by timid geneticists, are suppressing discussion of genetic variation. As Reich characterizes the position in his op-ed: “Average genetic differences among people grouped according to today’s racial terms are so trivial when it comes to any meaningful biological traits that those differences can be ignored.”
I simply don’t know any geneticists who believe this, and few who’d let it pass unchallenged. Many will point out, reasonably enough, that racial categories are an unreliable proxy for ancestry, with horrible social baggage. They’ll also point out that average differences between ancestral populations are typically very small compared to the variation within those populations, for most traits that scientists have tried to measure quantitatively. But scientists have continued to explore human variation, outside the grips of any orthodoxy.
In the days after the op-ed appeared, there were several rebuttals from fields outside genetics. In some cases, the corrective reactions of geneticists to these (admittedly sometimes flawed) rebuttals seemed swifter, noisier, and more vigorous than the corrective reactions of geneticists to Reich’s op-ed itself. Reich, too, published a follow-up in the Times, in which he clarified some of the language, but reiterated the argument against timid geneticists.
It’s common for natural scientists to eschew questions of linguistic semantics, preferring to steer debate to technical issues. This relates to how we define ourselves professionally: Science as a discipline seeks objective truth via empirically testable hypotheses, not subjective questions of public perception. “Now we’re just talking semantics” is a line that often signals imminent consensus, in friendly arguments among members of my profession.
But when speaking publicly about race, language matters. Regularly in American history, slavery, discrimination, and other forms of racism have been justified using distortions of science and pseudoscientific ideas. The U.S. program of eugenics was second only to Nazi Germany’s, which it directly inspired and informed.
In the op-ed, Reich emphasizes the importance of “laying out a rational framework for discussing differences among populations.” Otherwise, he writes, we “leave a vacuum that gets filled by pseudoscience.” That’s true, but if geneticists use the pseudoscientific terms ourselves, even carelessly, then we help this process along.
Ian Holmes is an associate professor of bioengineering at UC Berkeley.
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