Statistical noise or genetic certainty? White supremacist identity claims and the ambiguous objectivities of genetic ancestry
Anthropologue culturelle

(Université de Cambridge - Centre d’études latino-américaines)

During a week in November 2013, a minor Internet sensation was caused by a video that was doing the rounds on social networks. Originally posted by the Daily Mail Online, the clip was entitled “White supremacist Craig Cobb learns he’s 14% black.” It referred to an episode of the Trisha Show, a US talk show whose host, Trisha Goddard, a Black British woman, had invited Cobb to take a personalized DNA ancestry test. The Mail Online clip showed the moment at which Cobb’s results were revealed to him by Goddard, in front of a live studio audience. The camera focused in for a close-up of Cobb’s face, showing him staring intently at Goddard as she read the report: “eighty-six percent European. And er…” Goddard paused slightly for dramatic effect, and another guest, a Black woman wearing a kufi and sitting next to Cobb, started to laugh, slapping her knee and doubling forward with uncontained hilarity. The audience, also anticipating the punchline, began to jeer and clap, their voices rising together to a crescendo. “Give it to him!” exclaimed the woman in the kufi. “Fourteen percent sub-Saharan African!” declared Goddard. Amid continuing boos, heckles and laughter from the audience, Cobb could be seen raising a hand, shaking his head and grinning, undaunted: “wait a minute, wait minute… Hold on… Just wait a minute. This is called statistical noise,” he explained, knowingly. “Sweetheart,” countered Goddard,“ you have a little Black in you.”1

The clip was reposted online on numerous news outlets and blog sites, whose writers gleefully underlined the triumph of the hard facts of genetic science over Cobb’s racist ideology, grounded in archaic notions of racial “purity” and White supremacy. Cobb’s Wikipedia page was soon updated to include the DNA result in its opening summary. The incident was also taken by some liberal academics as an opportunity to illustrate the paradoxical effects of the United States’ historical racial classification system, in which having “one drop of Negro blood” was once the legal definition of Blackness. As ethnographer Yaba Blay explained in an article for CNN:

while Cobb might “look white” today, in 1813 or 1913, his 14% African ancestry would have been more than enough to render him black by law. In 2013, however, the irony of his heritage shows just how nuanced racial identity is beyond skin color.2

Cobb, however, did not accept the DNA ancestry result presented by Goddard, explaining to a Daily Mail reporter that he had “agreed to the test because I assumed it was science.” In the show’s aftermath, however, he described the AncestrybyDNA test, provided by the company DNA Diagnostics Center (DDC), as “a scientifically bankrupt procedure,” used by the TV show to “promote multiculturalism.”3In another interview with the Village Voice, Cobb labeled DDC a “shlock company” on account of their low-resolution genetic analysis and bad Internet reviews, and stated his intention to have his DNA reanalyzed by more reputable companies.4 A test provided by the business AncestryDNA (a subsidiary of, and today the leading provider of DNA ancestry tests globally) gave Cobb the result he was looking for: 100% European ancestry, including 57% “Europe West,” 34% “Ireland,” and various smaller percentages attributed to “Scandinavia,” “Iberian Peninsula,” “Great Britain” and “Europe East.”

Cobb wrote about his experience on the White supremacist web-forum Stormfront in a post dated March 10, 2015, in which he explained the technical superiority of the AncestryDNA test over the AncestrybyDNA analysis, based on a comparison of the products published online by the International Society of Genetic Genealogists (ISOGG).5 In his words: “The ‘ancestrybydna’ test checks for 176 alleles out of over 600,000. The ancestry.DNA test does over 500,000.” He went on to say:

I did all this – the original test – because I thought they would use a reliable test. It did occur to me that they might use junk science (I thought the chance relatively small, but there)… and in that event, my mental “pre-algorithm” was that there would be a huge outcry and denigration of myself, after which I would prove to doubters how – in a very personal sense and with the most serious of setbacks – Jew defamations, persecutions and manipulations work.

Apparently satisfied with the outcome of his AncestryDNA test, Cobb concluded his post with a plea for recognition:

I’d appreciate it if honorable men will stop calling me 14% black. […] I wish my Wiki could get edited. […] They currently have me listed as part African American. More Jew lies. I hope you can now see that at this late date in the matter.6

DNA ancestry testing is a phenomenon ripe with contradictions. The first direct-to-consumer (DTC) genetic ancestry testing companies appeared in the year 2000 in the United States and United Kingdom.7 Methodologically, these businesses draw on approaches developed in the fields of forensic and evolutionary genetics, taking advantage of geographically defined patterns of genetic variation found among contemporary human populations to make inferences about customers’ biogeographic origins, or to help reconstruct their biological family trees.8 Initially, these analyses relied either on “uniparental” testing – analyzing regions of mitochondrial DNA (mtDNA) and the Y-chromosome that are inherited maternally and paternally, each representing a single ancestral lineage in a person’s family tree – or on an approach called “admixture” testing, based on “ancestry informative markers” (AIMs) found across the genome and representing genetic inheritance from both parents (the AncestrybyDNA test is one such example).9 In 2007 the Californian biotech company 23andMe and the Icelandic biopharmaceutical company deCODE Genetics were among the first to pioneer a new variety of autosomal ancestry test, using genotype techniques that analyze hundreds of thousands of genetic variants (known as single nucleotide polymorphisms, SNPs) across the genome, representing a much fuller sampling of an individual’s genetic inheritance than the early uniparental and AIMs based tests.10 Since 2013, most DNA ancestry-testing companies worldwide have adopted these genotyping approaches, selling high-resolution admixture tests that link customers to dozens or even hundreds of “genetic ethnicities” around the world, for prices of US$100 or less.11

Over the past two decades, certain DNA ancestry testing services have received enthusiastic endorsements by those who regard these technologies as anathema to myths of racial or ethnic “purity.”12 Yet the industry has also been staunchly criticized for reinforcing the idea that racial and ethnic identities are – wholly or in part – genetic in nature.13 In recent years, companies offering fine-scale autosomal analyses have attempted to brand these products as tools for reconstructing “ethnic origins” for those who have become disconnected from their ancestral roots. Overall, though, the global DNA ancestry market remains disproportionately Euro-centric in the constitution of its reference datasets and customer bases, and some Native and Indigenous American activists, in particular, have condemned the industry for attempting to market their DNA under the guise of “curing” Western societies of their racial prejudices.14 Meanwhile, recent research demonstrating the interest of White nationalist communities in DNA ancestry testing has surprised many observers and seems to challenge assumptions about the antiracist potential of these technologies.15

In this article, I use the case of Craig Cobb’s DNA tests as a lens for addressing the question of how effectively genetic ancestry technologies can contribute to debunking ideologies of “racial purity.” I concentrate first on the technical aspects of the tests, demonstrating that, despite their reputed “objectivity,” the range of commercial DNA ancestry technologies on offer to the public, and the indeterminacy of their historical scope, make them a highly ambiguous tool for either supporting or refuting personal ancestry claims. In particular, I underline how, paradoxically, “scientific advances” in the DNA ancestry industry have made it more likely in recent years for consumers to receive results that could be construed as confirming claims of “racial purity”. In the second half of the paper, I explore how the “objectivity” of DNA ancestry as a marker of “race” is discussed and negotiated among different user communities, underlining the tensions between narratives of choice and the continuing salience of historical conventions in the definition of racial identities based on physical appearance and “blood” (ancestry). Similar to other researchers who have addressed this topic,[16 I show that genetic data are never regarded as an a priori truth, but rather assimilated selectively by test-takers – whether they hold to anti-essentialist or biological-essentialist conceptions of “race.” Finally, taking into account that White supremacist regimes function globally through a variety of constantly evolving discourses and structural arrangements (and not exclusively through discourses of “racial purity”) I conclude by arguing against the idea that DNA ancestry technologies can “automatically” challenge racisms in either their discursive or structural forms.

From “shlock companies” to “objective” science?

Let us begin by looking at how Cobb’s DNA results were received among geneticists who were familiar with the technology’s scope and limitations. In the aftermath of the Trisha Show episode, various journalists consulted experts to ask about the reliability of the “14% Sub-Saharan African” result. It is notable that most did so by referring to broad genetic principles, rather than the specificities of the AncestrybyDNA test. For instance, Neil Risch, director of the Institute for Human Genetics at the University of California, affirmed in an interview for NPR that “with genetic markers, you can actually do pretty well localizing people, even within a continent,” but pointed out that the results’ accuracy depended on the “thoroughness of the test.”17 Meanwhile, an article published on the “FactCheck” section of the Channel 4 News website (UK) included quotes from several geneticists on the matter. Neil Bradman, Chair of University College London (UCL)’s Centre for Genetic Anthropology, made no reference to the AncestrybyDNA test, but instead pointed out that it was “futile” for Cobb to argue against his result, since all humans “have a genetic ancestry that goes back to Africa.” Likewise a statement from Spencer Wells, director of the National Geographic’s not-for-profit genetic testing service, the Genographic Project, underlined the general points that “old-fashioned concepts of race are not only socially divisive, but scientifically wrong,” and that humans “do not fall neatly into physical categories some people call races.”18

In fact, the AncestrybyDNA test had been under critique for several years from geneticists, science and technology studies (STS) scholars, and genealogists, who signaled various technical and epistemological problems that could affect the test’s usefulness for estimating personal origins. Anthropologist Kim TallBear, for example, pointed to the test’s difficulty in discriminating between certain continental categories (e.g. Native American vs. East Asian, or Native American vs. European) based on the limited number of AIMs it used.19 Another drawback, noted by philosopher Lisa Gannett and anthropologist Duana Fullwiley, was the test’s inability to distinguish the age of the “admixture events” it detected.20 Making sense of results, therefore, depended heavily on the test-taker’s contextual knowledge of their family history, which, as we shall see, made the product a particularly ambiguous tool for inferring personal histories.

Ambiguous facts

The AncestrybyDNA test was originally developed by two American scientists, biological anthropologist Mark Shriver and molecular biologist Tony Frudakis, and it was put on sale to the public in 2002 by the company DNAPrint Genomics. For an initial price of $160, customers received a report estimating their ancestry composition in relation to four “major biogeographical ancestry groups” (“East Asian,” “IndoEuropean,” “Native American,” and “sub-Saharan African”), based on a survey of 75 AIMs found at various locations across the genome. DNAPrint was declared bankrupt in 2009 following the global financial crisis, and the AncestrybyDNA product was subsequently licensed to DDC, the company that processed Cobb’s test in 2013.21

In the patent application for their product, Frudakis and Shriver noted that the test’s composition of four “ancestral populations” corresponded to

a coalescence of a simplified human pedigree back in time to a point where populations were relatively isolated to the sub-Saharan African (sub-Saharan Africans), Europe and the Middle Eastern (IndoEuropeans), North/South American (Native Americans) and East Asian (East Asians) continental regions.22

The reference samples used to test the “ancestry informativeness” of the genetic markers representing these four putative ancestral populations were collected from contemporary groups, from Nigeria and Congo for the sub-Saharan African markers; the United States for the European markers; Japan and China for the East Asian markers; and “Nativos” from southern Mexico for the Native American markers. As Gannett has noted, the underlying assumption was that these modern groups were relatively genetically “unmixed,” their members united by “well-delineated ancestral ties to the ‘founder groups’ and straightforward histories of migration as peoples.”23 Meanwhile, the genetic compositions of individuals living in geographically intermediary positions between these “extreme” genetic coordinates of the Old World were expected to present as a mixture of these groups, to reflect the “complex” ancient migrations and admixtures that have taken place between neighboring human populations over numerous millennia. Hence, explained Frudakis and Shriver, a present-day Russian individual could logically be expected to have around 10% East Asian genetic ancestry, owing to the influence of “ancient admixture” dating back some 18,000 years.24


In contrast, Frudakis and Shriver suggested, signs of genetic admixture in individuals living in countries whose histories have been marked by European colonization were much more likely to be the result of recent “blending,” arising in the past five hundred years or so (an apparent exception to this rule were European-descendant Americans, who were used to provide the “European” reference population for the test). However the only way to verify the dating of this admixture, they indicated, was with the support of genealogical information:

for some genealogists, depending on the family tree, evidence may strongly suggest that the mechanism of admixture is from recent events. As such, for a person whose family has paper evidence of an American Indian great grandparent, a 10% Native American admixture result according to the BGA test can indicates the event likely arose due to recent admixture. In comparison, for a person of confirmed and homogeneous European ancestry, a 10% Native American admixture indicates the event likely arose due to an ancient admixture.25


Another issue mentioned by Frudakis and Shriver was the test’s standard error margin, which they reported was typically between 1> and 5 percent.26 This was referred to in one version of the AncestrybyDNA user manual as “statistical noise” (the term used by Cobb to reject his sub-Saharan African ancestry result) and was contrasted with “real” admixture, the phenomenon that the test sought to detect.27 Ancestry assignation errors occurred in the test because, for the most part, the AIMs it used were not exclusive to a single human population, but rather were found in higher frequencies among some populations than others, making the results probabilistic (within a given margin) rather than definitive. Instances of the test miscategorizing known Native American ancestry as “East Asian” were also reported by Frudakis and Shriver during their initial experiments, in which they sought to verify the panel’s accuracy at estimating recent admixture by comparing the results to test-takers’ known genealogies.28 In their analysis, such errors did not constitute “a ‘wrong’ answer in a scientific sense,” but could be logically explained by the close genetic link between contemporary East Asian and Native American populations, whose ancestors arrived in the Americas from East Asia by crossing the Bering land bridge in a series of migrations between 10,000 and 25,000 years ago.29

Due to this issue, however, and the test’s inability to distinguish between ancient and recent admixture, Frudakis and Shriver advised that negative results were likely to serve as more conclusive evidence than positive ones for individuals attempting to verify theories about their recent ancestry:

for example, if there is circumstantial, but low quality, data suggesting a pure blood African great-grandfather, and the BGA test reveals 100% IndoEuropean, then the rumor would be discounted (taking into account the genetic law of independent assortment, which would make such a result possible, but unlikely if the data was in fact correct). However, if a person’s family is suspected to have had a Chinese great grandfather, one cannot prove it from a 20% East Asian admixture result, since it is not possible to distinguish exogamous [i.e. recent] admixture from ancient admixture.30

According to these guidelines, the best way to confirm or discard the hypothesis about Cobb’s recent ancestry would be to conduct further genealogical research to look for firm evidence of any Black ancestors. Nonetheless, such historical clues are difficult to recover, precisely because US racial doctrines were designed to categorize “mixed” individuals under “non-White” groups, so that extreme stigma became attached to the idea of “racial mixture” within White US family lineages.31 Thus, individuals of African ancestry who “passed for White” may have been careful to conceal their ancestry from their new families, in order to integrate fully into White society; alternatively, descendants of such individuals could have posthumously modified their family trees or omitted these ancestors from oral histories to preserve the myth of ancestral “purity.”

Evolving technologies

The new generation of fine-scale autosomal analyses released by companies like 23andMe, AncestryDNA, and FamilyTreeDNA,32 have been designed to overcome some of the issues of category assignation and historical scale presented by early admixture tests like AncestrybyDNA. Whereas Frudakis and Shriver’s analysis used a handful of geographically distant groups as reference populations, each representing a continental “ancestral population,” the new autosomal tests rely on “dense” sampling techniques across numerous populations from broad geographical regions. An early example of this methodology was presented in a 2008 study of the genetic structure of European populations, led by evolutionary biologist John Novembre of the University of California, which demonstrated that, based on selective sampling techniques, fine-scale genetic structure could be detected even among populations with “low average levels of genetic differentiation,” in ways that suggested “a close correspondence between genetic and geographical distances.”33

AncestryDNA’s “genetic ethnicity” test first went on sale in May 2012. A press release at the time stated that the test analyzed “a person’s genome at over 700,000 marker locations,” and helped “determine geographic and ethnic origins by comparing test-takers’ unique DNA signatures to the DNA of people from across the globe […]. The current version of the test includes 20 worldwide geographical and ethnic categories, including six regions in Europe, five regions in Africa, and Native American.”34 The analysis draws on a unique reference dataset: a collection of 100,000 DNA samples taken from living populations around the world, each accompanied by detailed genealogical pedigrees.35 This dataset was compiled between 1999 and 2010 through the efforts of scientists and volunteers associated with the Sorenson Molecular Genealogy Foundation (SMGF), an initiative funded by Mormon billionaire James LeVoy Sorenson, in the aim of producing a database with global genetic coverage.36 The collection was originally made available for public access through the website GeneTree, where individuals could upload their own genetic data and compare them to “lineages” stored in the database.37 After Sorenson passed away in 2010, however, the collection was acquired by Utah-based genealogy giant, who used it to form the basis of its new AncestryDNA product.

A whitepaper published on the AncestryDNA website describes the scientific process behind the “genetic ethnicity” test.38 The first step is to select reference samples from the SMGF dataset and other public databases, to represent a sampling of “worldwide populations.” Typically, the samples for each target region come from individuals who are not closely related, and whose ancestry is relatively “non-admixed” (for instance, people whose four grandparents were all born in the same country). Next, the reference samples are genotyped and the data are “cleaned.” This is done using principal components analysis (PCA), in which each DNA sample is plotted as a point on a graph, such that its distance from all other plotted samples reflects their overall genetic distance to one another (a measure that often also reflects geographical distance). These plots allow scientists to identify and remove samples that appear as outliers, something that could happen because certain individuals within a cohort are too closely related, or because their genetic ancestry contradicts their pedigree information, among other reasons. When the “clean” data are mapped again onto a PCA plot, they should ideally display as fairly distinct, if slightly overlapping, clusters. The scientists use these clusters to identify a number of “genetic populations,” which will form the basis for the test’s constituent “genetic ethnicities.” Subsequently, a series of tests are conducted to check the “ethnicity”-predictive performance of each sample within the newly narrowed down reference database; once again, any outliers are removed.

The AncestryDNA analysis is designed based on the assumption that the vast majority of customers’ DNA will be a mixture of various “ethnicities,” owing either to recent admixture events (dating from the past five hundred to one thousand years), or to deeper histories of migration and admixture (dating from beyond the past millennium). Clients’ admixture proportions are calculated by an algorithm that analyses allele frequencies at hundreds of thousands of positions across the genome. The process of ancestry assignment between neighboring regions is highly probabilistic, and relies on collective “signals” across many genomic markers (single nucleotide polymorphisms, SNPs).39 Thus, there is no such thing as a single “French” or “Japanese” genomic marker that can trace a person’s ancestry categorically to those populations.40

The AncestryDNA test – like other similar products that appeared on the market around the same time, for instance, 23andMe’s autosomal ancestry composition test, and FamilyTreeDNA’s myOrigins test – represents significant technical and methodological advances in relation to the earlier generation of admixture tests, particularly with regards to the geographic scale on which they claimed to estimate customers’ ancestry. The first version of the AncestryDNA test included 26 “worldwide” regions of varying geographic specificity (e.g. “Scandinavia,” “European Jewish,” “Asia East,” “Benin/Togo,” “Africa North”). These were chosen both pragmatically (based on the contents of the reference database and the “ethnicity”-predictive performance of the samples), and strategically, keeping in mind the composition of’s existing clients (largely European or Euro-descendant Americans), as well as “new” target demographics such as African Americans.41 Hence, the “global” coverage given by these tests tended, in reality, to be uneven and often quite patchy: for example, there were nine “genetic ethnicities” each for Europe and Africa, compared with just three for Asia, one for the Americas, and none for Australasia.

It is notable, however, that most of these companies continued to group their reference populations by continental category. Typically, DNA test-takers receive their ancestry report in the form of a world map, shaded with colored oblongs indicating their regions or “ethnicities” of ancestry, and accompanied by a table showing the breakdown of their ancestry percentages by region. 23andMe and FamilyTreeDNA both opted to color-code their results, allotting a single color to each continental group and (in the case of 23andMe) shading their sub-continental populations in different hues of the same color (see Images 1 and 2). For its part, AncestryDNA assigned colors to each genetic population at random, but presented the results in a stacked table that was organized by continental groupings, so clients saw first their overall continental percentages, and then the more detailed “ethnic” breakdown for each region (see Image 3).42 This, for instance, is how Craig Cobb received his own “100% European” ancestry result.

As Peter Wade has remarked, although autosomal DNA ancestry tests tend to express clients’ ancestry as a mixture of contributions from different “genetic populations,” they nonetheless “inevitably entrain concepts of purity and wholeness, as the notional bounded antecedents that give rise to the mixture.”43 Thus, in the process described above, clients’ admixture proportions are calculated in reference to collections of DNA samples that have been purposely “cleaned” (one could also say, “purified”) in order to give the impression of a clear genetic signal, thereby linking together DNA markers with “distinct” populations and geographic territories. Nonetheless, as Wade notes, this is always a relative purity, which hides within it deeper histories of mixture and migration.44 In the case of the AncestryDNA test (and others like it), the overall aim of the product is to reflect back to customers an account of their ancestry that corresponds to a relatively recent genealogical timeframe. Hence, the labels used to describe different “genetic ethnicities” or “ancestries” typically.

Author’s autosomal admixture results

Author’s autosomal admixture results from FamilyTreeDNA’s myOrigins test, 2014

Author’s autosomal admixture results

Author’s autosomal admixture results from 23andMe’s ancestry composition test, 2016

Author’s autosomal admixture results

Author’s autosomal admixture results from AncestryDNA’s genetic ethnicity test, 2014

The difficulty of accurately historicizing DNA ancestry results is recognized by the AncestryDNA scientists in their whitepaper. They mention that one way of testing the efficacy of the test is to compare the results it produces with the pedigrees held in the SMGF database (or, for instance, those of customers who have uploaded detailed family trees to their profiles).45 However, they state:

pedigrees contain information that is quite different from what we are estimating at AncestryDNA. They show only the locations of a sample’s known ancestors, whereas in genetic ethnicity estimation, we are attempting to estimate the unknown amount of DNA actually inherited from all of a sample’s ancestors. Genetic estimates of ethnicity also go back thousands of years, beyond the end of a pedigree paper trail. Regions identified as “populations” in a pedigree may have been very different thousands of years ago, and so may be represented differently in a genetic ethnicity estimate.46


The focus on a recent historical timeframe, roughly corresponding to the period of European colonialism, responds largely to American customers’ interests in uncovering their ancestors’ geographic origins directly before their arrival in the “New World.”47 This is also the period in which the modern conception of human “races,” as referring to broad continental groups, was developed and deployed as a way of categorizing individuals in colonial societies, ruling over, for instance, who could reproduce with whom, and what legal and social status their offspring would inherit. If we view race as a biocultural phenomenon – i.e. as the product of colonial historical systems and racist worldviews oriented toward reproducing ostensibly “natural” differences via the management of populations – then the fact that “race-like” categories tend to emerge in these reports may be understood as a reflection of these histories of racialization.48 Nonetheless, understanding the results in this way requires appropriate historical and theoretical contextualization – something that many DNA ancestry companies fail to provide. Hence, categories like “European” may appear to clients as naturally bounded and historically stable entities, rather than as a product of recent histories of colonial and racial projects. Indeed, this is the reading that White nationalists prefer to give to such reports, enabling these data to feed back into their claims about the absolute and biologically-rooted nature of racial difference.

Negotiating ancestry

So far, I have shown how differing techniques of genetic analysis – reflecting an interest in varying historical and regional scales for ancestry estimation – were able to produce two different accounts of Craig Cobb’s ancestry. Yet the story does not end here. Social science studies into the reception of DNA ancestry data among different public users and in various cultural contexts have shown that genomic knowledge is always subject to socially and ideologically informed processes of translation and interpretation, which condition how test-takers relate their DNA results to personal narratives of identity.49 Like other forms of social identity, DNA-based claims to racial or ethnic affiliation invoke collective and necessarily reciprocal processes of affirmation and ascription, election and imposition. Thus, test-takers often consult with particular communities and “gatekeepers” to establish the relevance of their DNA data to a claimed identity.50 Typically, these negotiations also seek to establish the objectivity of the genetic results, through comparison with other forms of contextual knowledge. These can range from personal sources of information (e.g. existing oral or documentary accounts of family histories) to broader, common-sense ideas about identity and ancestry, for instance rooted in national myths of identity or particular ideologies about race.51

In the United States, the conventional distinction between Whiteness and Blackness refers to ancestry. This convention is rooted in slavery and the colonial concern with defining who may or may not be enslaved (with Whiteness being intrinsically associated with “natural” freedom, and Blackness with “natural” slavery).52 The definition of the “color line” has varied over time: hence, at different historical periods in the state of Virginia, having “one-fourth Negro blood,” “one-sixteenth or more of Negro blood,” or “any ascertainable Negro blood” were the benchmarks for defining an individual as legally Black.53 Today, many critical race theorists argue that Black American identities are no longer primarily informed by the biological logic of “drops of blood,” but rather by social mechanisms of self-ascription and communal recognition. Hence, in her response to Cobb’s DNA test results, ethnographer Yaba Blay – whose recent book (1)ne Drop explores conceptions of Blackness among light-skinned and “ambiguous-looking” individuals who identify as Black or African-descendant – explained:

blackness, as an identity and as a lived experience, is much more complex and nuanced than any number of drops on a family tree. Blackness is as much about who creates you as it is about what you make of yourself.

So while I was thoroughly amused by the sight of Craig Cobb’s face when he learned that he, too, is “of African descent,” I am clear that those DNA test results do not magically make him black; no number of drops ever could.54

Blay’s argument underlines the importance of choice, as well as convention, in the contemporary definition of racial identities. This is a theme that has been underlined by other scholars who have studied users’ responses to DNA ancestry technologies, as well as in my own research into the impacts of DNA testing upon the racial and ethnic affiliations of Brazilian and US test-takers.55 Some of the White US test-takers I interviewed, for instance, were attributed small percentages of African ancestry in their DNA results. Although conventionally this may be seen as grounds for reclassifying themselves as “Black,” none of the individuals in question said that the test had changed the way they identified racially. Unlike Cobb, these test-takers recognized their African admixture results as valid, and some had even conducted genealogical research to try and identify where in their family tree this ancestry originated. However, they felt that they could not claim a Black identity since (as one individual put it) “it’s not something that I have ever lived with or identified with, and neither has anyone in my family.”56 These responses support Blay’s claim that, for many individuals in the United States today, Blackness is not merely reducible to “drops of blood” or percentages of DNA; it is also a form of cultural memory that must be reaffirmed repeatedly from one generation to another in order to retain a sense of social authenticity. This becomes particularly important when the traces of this racialized origin no longer “show” on the surface of the body; in these cases, Blackness becomes, above all, an elective identity.


The relationship between DNA ancestry and racial identities is perceived slightly differently in Latin American societies like Brazil, which are marked by histories of intense “racial” mixture (mestiçagem or miscigenação in Portuguese) and eugenic ideologies of racial Whitening (embranquecimento/branqueamento). Thus, the Brazilian test-takers I interviewed consistently made a distinction between their genetic ancestry percentages (which some saw as akin to a measure of their “biological race”) and their “color” (cor in Portuguese, a term that encompasses skin tone as well as other racialized phenotypical traits such as hair texture, eye color, and the shape of the nose and lips). They emphasized that it was “color,” not genetic ancestry, that mediated their experiences of racism (or lack thereof), and which therefore influenced the way they identified racially, for instance on official forms.57 Nonetheless, those individuals who were actively engaged in Black political movements or “Afro” cultural groups tended to view Blackness as rooted less in either genetic ancestry or color than in a sense of personal identification with Afro-Brazilian history and culture. Thus, some light-skinned DNA test-takers assumed an “Afro” identity based on their affinity to a particular grandparent or relative who had passed down stories of their family’s Black roots.58 Efforts to retain such memories of Blackness can be understood as acts of resistance against Brazil’s Whitening ideology, which was developed in the late nineteenth and early twentieth century with the aim of “purifying” the nation of its African and Indigenous “racial” elements. While this ideology has waned over time, its influence still drives forms of anti-Black racism in Brazil today.59

Challenging or confirming Whiteness?

Relationships between DNA ancestry data and forms of racial identification are therefore always socially and politically mediated and read through the lens of both personal family histories and communal racial conventions. Craig Cobb, for his part, was keen to negotiate his DNA results among his own chosen community of White supremacists, a group whose unifying ideology centers on beliefs in the need to protect the genetic purity of the “White race.” Initially, members of this group seemed ambivalent about Cobb’s alleged “sub-Saharan African ancestry.” One thread about the incident, posted on the Stormfront forum soon after Cobb’s appearance on the Trisha Show, barely mentioned the DNA results. Some forum members were clearly sympathetic to Cobb, sharing their opinions that the show was “rigged against him,” and confirming his claimed identity as “a courageous, honest, racially loyal White man.” The rest of the comments mainly dwelled on whether Cobb was “misrepresenting” or “damaging” the White nationalist community by openly labeling himself a neo-Nazi (a form of branding that some members feared could scare off possible recruits by making the community seem “too extreme”).60

In 2015, when Cobb posted his AncestryDNA results to another Stormfront thread, the reactions of members to the new genetic report were overwhelmingly positive. Several members congratulated Cobb on proving his Whiteness, and by the same token reinforcing the racist principles held by the community, for instance the idea that a person can be 100% genetically White, or that the presence of Black or Jewish “blood” always “shows” in an individual’s physical appearance or behavior, for those who know how to detect it. As one member stated: “I knew [Mr. Cobb was 100% European] if he was 14 percent black you would be able to tell.” Another added “these contemptible people that ‘proved’ Craig was an octaroon only undermine science with their nonsense. Anybody with an ounce of common sense could see the result on that idiotic program was a total fabrication.”61

These behaviors echo the findings of a broader sociological study, conducted by Aaron Panofsky and Joan Donovan, into the reactions of Stormfront members to personal DNA ancestry test results posted within the community – some of which were read as confirming test-takers’ White racial identities, while others were seen as contradicting these claims.62 Despite the community forum’s strict membership criteria (“non-Jewish people of wholly European descent. No exceptions”), Panofsky and Donovan observed a large number of supportive responses to test-takers whose genetic ancestry data were perceived as challenging their White racial identity. These sympathetic members mobilized a variety of strategies aimed at refuting or reinterpreting these “undesirable” results: some included casting doubt on the reliability of the test itself, based on the assertion that many DNA ancestry-testing companies are “run by Jews” or “part of a liberal conspiracy,” and that they routinely attribute small percentages of “non-White” ancestry to American test-takers, to “spread multiculturalism and make Whites think that they are racially mixed.”63 Members suggested that test-takers should have their DNA reanalyzed using alternative services, and recommended scientists thought to be sympathetic to the White nationalist cause, or open-source DNA comparison platforms such as GEDmatch,64which were assumed to be less affected by “multicultural biases” than the mainstream commercial companies. Another approach was to assume category errors in the labeling of the genetic data, so that racially “suspect” populations could be reinterpreted as definitively “Caucasian” ones.


Overall, though, Panofsky and Donovan observed that DNA ancestry testing was perceived as a threat to the biological-essentialist notions of race that underpin White nationalist ideologies. The problem, noted by some forum members, was that initial indications that most individuals of European descent have small percentages of non-European genetic admixture would mean that many members would no longer be classified as racially “pure” under the current community standards. Yet for the most part these technologies are not causing individuals to abandon their racial beliefs; instead, White nationalist communities are attempting to redefine the boundaries of Whiteness. Some propose moving away from biological-essentialist definitions, suggesting that cultural and political conceptions of Whiteness could provide a more appropriate benchmark for membership. As one Stormfront member stated: “if you look White, live White, identify White, if your grand-parents and great-grand-parents looked White/lived White/identified White--that is often sufficient.”65 Conversely, others herald the possibility of identifying the genetic variants underpinning the physical, behavioral and cognitive traits deemed to characterize Whiteness, thereby bringing genetic essentialism in through the back door.66 As Panofsky and Donovan note, many DNA ancestry companies already offer genetic trait predictions “from hair and eye color to tasting preferences to IQ”67– tools that will probably be readily appropriated by these communities to form new tests of “genetic Whiteness.”


Blood and soil

Panofsky and Donovan’s study underscores the fundamental mutability of racist ideologies, and the ability of their proponents to adapt their doctrines to scientific data, and vice versa. While in some cases DNA tests can lead individuals to question their existing notions of ancestry, and even change their ontological understandings of race, for those who are heavily committed to ideologies of racial superiority these outcomes seem less probable. What’s more, as Cobb’s example demonstrates, the different methodologies that are employed across DNA testing services provide numerous options for obtaining the desired result. It should be noted that retesting one’s DNA with various companies is a relatively common practice that goes beyond White nationalist communities. In my own research, however, I found that for most DNA test-takers the objective of retesting was usually to gain a more rounded perspective on their ancestry, and compensate for the technical limitations of any given test (e.g. database size and contents, DNA markers surveyed) – rather than to prove one’s claimed racial identity.68

It should also be noted that quests for racial “purity” are not the only ways in which DNA ancestry data have been used to support agendas of racial or ethnic supremacy. Jenny Reardon and Kim TallBear have likened the fervor of “Western” scientists for collecting the DNA of Indigenous groups to the “old and familiar position of [Europeans] making a moral claim on the natural resources of indigenous peoples.”69 Native and Indigenous American activists and scholars from the United States and Canada have vehemently protested the inclusion of Native and Indigenous American DNA samples in commercial ancestry-testing databases, signaling that these technologies are frequently being used to legitimate claims upon their identities and political resources by non-Indigenous people. Such practices could lead to legal redefinitions of “Nativeness,” emphasizing racial notions of ancestry over the importance attributed to social and cultural relations among tribal conceptions of identity.70 Meanwhile, Darryl Leroux has shown how DNA-testing services offering “Native American” ancestry tests have been used to bolster the efforts of French Québecois settler-descendants to gain legal recognition as an “Aboriginal” group, with attendant political rights. In Leroux’s words, tracing their family lineages to distant Native American ancestors “provides the basis for white settlers to become Indigenous in a manner that undermines Indigenous sovereignty and self-determination.”71 Meanwhile, in the United Kingdom and other European countries, ethnic nationalists have attempted to coopt population genetic studies, and the supposed biological particularities they identify among “native” European populations, to argue that the latter should be accorded aboriginal status and protected from the corrupting influence of “foreign” migrants.72

For geographer Catherine Nash, the dichotomy between “autochthonous” and “foreign” (or “pure” and “mixed”) groups is baked into the theoretical foundations of population genetics, which frequently focuses on mapping genetic variation in relation to geographically defined human groups. Nash states:

the idea that a sequence of DNA has a geographical origin in turn implies that places – localities, regions, countries, and continents – have a particular genetic character and that the people who live in that place share that character and differ genetically to varying degrees from people in other places. In this line of thinking, those who are in a specific place but are genetically different from the “indigenous” inhabitants have other natural genetic ancestral places and, therefore, at some fundamental level, naturally belong elsewhere.73

Politically, this logic is double-edged: while some historically oppressed groups (for instance the Uros in Peru and the Ainu in Japan) have attempted to leverage notions of genetic differentiation to support their claims for political recognition as “ethnically distinct” groups, in practice DNA data may also be used to discredit claims to ethnic particularity if a “sufficient” level of genetic homogeneity is not found.74 Hence, during the decade-long polemic over the introduction of racially-targeted affirmative action initiatives in Brazil, genetic ancestry studies were frequently co-opted by right-wing commentators to challenge the political legitimacy of Black activist groups, who championed the policies as a means to tackle structural forms of racism and social inequality by boosting the admissions of Black students at public universities. These commentators drew upon DNA studies that emphasized the mixed ancestry of all Brazilians, regardless of their “color” – a fact, some claimed, which made it impossible to establish objectively who should be eligible for affirmative actions, since a person could be dark-skinned with “African” features but have a large proportion of European genetic ancestry, or vice versa.75 Although the quotas passed into federal law in 2012, more recently, fears that phenotypically White Brazilians may be undermining the effectiveness of quotas initiatives by presenting DNA reports or other genealogical data as evidence of their African ancestry (a phenomenon that has been dubbed “racial fraud” by some Black activists) has led to the publication of new policy guidelines that double down on physical appearance rather than ancestry as the main grounds for gaining access to racially-targeted affirmative action programs.76


That DNA ancestry testing can serve as a powerful tool for deconstructing racist ideologies is often taken for granted. Yet my argument in this paper supports the idea that DNA technologies remain a “double-edged sword” when used to try and prove the invalidity of biological-essentialist conceptions of race, through the lens of personal genetic ancestry.77

One issue relates to the variety of genetic ancestry analyses that are currently available to the public: differences in the composition of reference databases and the DNA markers analyzed can produce vastly differing accounts of the same person’s ancestry. Consequently, individuals looking to prove a particular narrative of ancestry are able to re-test their DNA until they find a version that “fits.” Commercial DNA ancestry technologies are also constantly evolving, in ways that seek to meet the interests of target customer bases. In the past decade, DNA ancestry testing companies (particularly those catering primarily to North American clients) have attempted to refine their analyses to reflect test-takers’ “ethnic” origins on a relatively recent genealogical timescale, roughly corresponding to the period of European colonialism and the emergence of modern racial categories. Their ancestry-estimation algorithms attempt to filter out traces of “deeper” ancestral mixtures, with the effect that these DNA ancestry results are more likely to coincide with clients’ prior expectations regarding their ethnic and racial makeup (vis-à-vis, for instance, earlier AIMs-based tests, which are still offered by some businesses). This raises important questions about the objectivity of commercial DNA tests as a “scientific” measure of ancestry. As Jenny Reardon has asked, “can genetic ancestry tests – tests based on databases shaped by particular economic and political orders – be deemed objective? On what grounds?”78

Despite these changes, many companies continue to arrange their results using race-like taxonomies (for instance, breaking down “ancestry proportions” first into continental groups, followed by sub-continental categories), making it possible for clients to be informed that they are “100 per cent European,” for example. Such reports are eminently susceptible to racist interpretations; as Panofsky and Donovan state, “white nationalists view the ‘100% European’ results that some receive as a demonstration that the ideal of white, European ‘purity’ is an empirical reality for many, pace the liberal claim that ‘everyone is mixed.’”79

On the other hand, taken collectively, such results can also say something about the way racial difference has been constructed and reproduced historically through the management of sex, space, and kinship structures in colonial and slavocratic societies. In this respect, some scholars have argued that race cannot be understood as merely a social construction, since the processes of racialization that accompanied and legitimated systems of slavery and colonialism have left their imprint in the very genomics of modern American and Caribbean populations.80 To assert this, however, is by no means to endorse biological-essentialist conceptions of race. Instead of proposing that “races” are naturally occurring genetic structures that govern human behaviors and personal destinies, biocultural paradigms seek firmly to “situate human biodiversity within a sociocultural framework, in effect reuniting culture and biology by embedding biology in society and culture.”81 Thus, the fact that some American White supremacists may indeed receive “100 per cent European” ancestry results can be understood as a consequence of the taboo on racial mixture in colonial and postcolonial North America – but also as a result of the efficacy of the “one drop rule” in designating any progeny of de facto interracial relations as racially “Black,” and thus removing these individuals from White genealogies. Meanwhile, the fact that some White Americans do receive small percentages of African genetic ancestry may be understood as a relic of the historical attempts by light-skinned Blacks to “pass as White,” and thereby escape slavery and systemic racism.

In this article I have focused particularly on reactions to genetic ancestry data among North American White nationalists, using the example of Craig Cobb’s contradictory DNA results as a case study. Nonetheless, it is important to signal that ideologies of racial and ethnic supremacy are by no means limited to notions of genetic “purity.” In Latin America, White supremacist ideologies have been mobilized with great success through eugenic notions of racial mixture.82 Interestingly, Panofsky and Donovan have noted that some North American White supremacists are debating adopting similar conceptions of Whiteness, based on the principle of “diluting away” traces of past racial mixture through selective mating – a process that could ostensibly be tracked using DNA ancestry technologies.83 This speaks volumes about the mutability of racist and ethnic nationalist doctrines, which are amply capable of adapting to mainstream scientific theories and technologies in ways that preserve intact their agendas of racial domination.

Finally, I want to point out that in this paper I have limited my analysis to the question of how effective DNA ancestry technologies are for debunking racist ideologies. However, forms of racism are commonly understood by social scientists to extend beyond mere beliefs in racial “purity” and supremacy. They are structural and systemic – the result of how racial ideologies have organized societies in ways that perpetuate inequalities among racialized groups.84 With regards to tackling structural forms of racism, the antiracist potential of DNA ancestry tests remains ambiguous. In Brazil, for example, results of studies into the nation’s genetic admixture have been used to challenge and discredit the efforts of antiracist campaigners. Elsewhere, Indigenous groups have raised concerns that DNA data are being used to misappropriate their identities and erode their hard-won rights to political resources, as historically oppressed minorities. In these contexts, well-meaning aphorisms such as “we are all genetically mixed” or “we are all migrants” can become ways of evading or even obstructing the political action needed to address the societal inequalities on which racisms thrive.

Unfold notes and references
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Collins, “EXCLUSIVE: Watch the Moment White Supremacist...”

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Cobb, “Craig Cobb’s DNA Results.”

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Donn Devine, “Solving the Mystery: DNA Tests for Your Research,” Ancestry 18, no. 5 (2000): 47–49; Catherine Nash, “Genetic Kinship,” Cultural Studies 18, no. 1 (2004): 1–33.

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The genetic factors underpinning these population structures are explored in greater depth in Hiroki Oota, “La diversité génétique humaine et les facteurs socio-culturels,” Politika, July 21, 2021.

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Mark D. Shriver and Rick A. Kittles, “Genetic Ancestry and the Search for Personalized Genetic Histories,” Nature Reviews 5 (2004): 611–18; Jean-Luc Bonniol and Pierre Darlu, “L’ADN au service d’une nouvelle quête des ancêtres ?,” Civilisations 63, no. 1 & 2 (2014): 201–19.

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“Autosomal” refers to the autosomes, i.e. the 22 pairs of numbered chromosomes that make up the human genome, and which are inherited by recombination (this excludes one pair of sex chromosomes, X and Y). On the development of 23andMe’s and deCODE’s autosomal tests, see: Gísli Pálsson, “Decode Me! Anthropology and Personal Genomics,” Current Anthropology 53, no. 5 (2012): S185–95.

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Claude-Olivier Doron and Jean-Paul Lallemand-Stempak, “Interpréter la diversité humaine. entretien avec Bertrand Jordan,” La Vie des Idées, February 25, 2014; Sarah Abel, “A la recherche des identités transatlantiques. Des boucles conceptuelles au croisement de la société, l’histoire et la génétique,” Nuevo Mundo Mundos Nuevos, Colloques, October 10, 2016; Sarah Abel, Permanent Markers: Race, Ancestry, and the Body after the Genome (Chapel Hill: University of North Carolina Press, 2022), 89–113.

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Sarah Abel, “Of African Descent? Blackness and the Concept of Origins in Cultural Perspective,” Genealogy 2, no. 1 (2018),

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Kim TallBear, “DNA, Blood, and Racializing the Tribe,” Wicazo SA Review 18, no. 1 (Spring 2003): 81–107; Dorothy Roberts, “Tracing Racial Roots,” in Fatal Invention: How Science, Politics, and Big Business Re-Create Race in the Twenty-First Century (New York: New Press, 2011), 226–57.

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Dieter Holger, “DNA Testing for Ancestry Is More Detailed for White People. Here’s Why, and How It’s Changing,” PCWorld, December 4, 2018; Jenny Reardon and Kim TallBear, “Your DNA Is Our History: Genomics, Anthropology, and the Construction of Whiteness as Property,” Current Anthropology 53, no. 5 (2012): S233–45.

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Élodie Grossi and Joan Donovan, “Hate in the Blood: White Supremacists’ Use of DNA Ancestry Tests,” The Activist History Review, October 20, 2017; Vasile Stănescu, “‘White Power Milk’: Milk, Dietary Racism, and the ‘Alt-Right,’” Animal Studies Journal 7, no. 2 (2018): 103–28; Aaron Panofsky and Joan Donovan, “Genetic Ancestry Testing among White Nationalists: From Identity Repair to Citizen Science,” Social Studies of Science 49, no. 5 (2019): 653–81,; Alexandros Mittos et al., “‘And We Will Fight For Our Race!’ A Measurement Study of Genetic Testing Conversations on Reddit and 4chan,” 2019; Aaron Panofsky, Kushan Dasgupta, and Nicole Iturriaga, “How White Nationalists Mobilize Genetics: From Genetic Ancestry and Human Biodiversity to Counterscience and Metapolitics,” American Journal of Physical Anthropology 175, no. 2 (2021): 387–98,

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For example Alondra Nelson, “Bio Science: Genetic Genealogy Testing and the Pursuit of African Ancestry,” Social Studies of Science 38, no. 5 (2008): 759–83; Wendy D. Roth and Biorn Ivemark, “Genetic Options: The Impact of Genetic Ancestry Testing on Consumers’ Racial and Ethnic Identities,” American Journal of Sociology 124, no. 1 (2018): 150–84,; Panofsky and Donovan, “Genetic Ancestry Testing among White Nationalists.”

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Kim TallBear, Native American DNA: Tribal Belonging and the False Promise of Genetic Science (Minneapolis: University of Minnesota Press, 2013), 73.

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Duana Fullwiley, “The Biologistical Construction of Race: ‘Admixture’ Technology and the New Genetic Medicine,” Social Studies of Science 38, no. 5 (2008): 695–735; Lisa Gannett, “Biogeographical Ancestry and Race,” Studies in History and Philosophy of Biological and Biomedical Sciences 47 (2014): 173–84.

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In recent years, DDC has rebranded its AncestrybyDNA test, and now sells it under the label HomeDNA Starter Ancestry Test. The test is also available from, where it is promoted as being endorsed by the Maury Show, a US talk show that shares the same executive producer as the Trisha Goddard Show. See Margaret O’Brien, “What Happened To AncestrybyDNA?,” Data Mining DNA (blog), December 30, 2020.

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Tony N. Frudakis and Mark D. Shriver, Compositions and methods for inferring ancestry, US Patent and Trademark Office 20040229231 (San Diego, CA, filed August 19, 2003, and issued November 18, 2004), para. 0235.

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Gannett, “Biogeographical Ancestry and Race,” 179.

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Frudakis and Shriver, Compositions and methods for inferring ancestry, paras. 0276–0277.

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Frudakis and Shriver, para. 0280.

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Frudakis and Shriver, para. 0190.

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Gannett, “Biogeographical Ancestry and Race,” 180.

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See also TallBear, Native American DNA, 73.

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Frudakis and Shriver, Compositions and methods for inferring ancestry, para. 0258; see also J. Víctor Moreno-Mayar et al., “Terminal Pleistocene Alaskan Genome Reveals First Founding Population of Native Americans,” Nature 553 (2018): 203; David Reich et al., “Reconstructing Native American Population History,” Nature 488 (2012): 370–75.

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Frudakis and Shriver, Compositions and methods for inferring ancestry, 0281.

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Elaine Pinderhughes, “Black Genealogy Revisited: Restorying an African American Family,” in Re-Visioning Family Therapy, ed. M. McGoldrick (New York: Guilford, 1998), 114–34; Edward Ball, Slaves in the Family (New York: Farrar, Straus and Giroux, 1998); Sarah Abel, “Linked Descendants: Genetic-Genealogical Practices and the Refusal of Ignorance around Slavery,” Science, Technology, & Human Values, 2021,

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FamilyTreeDNA is a Houston-based company that was among the first to begin offering personalized DNA ancestry tests to the public in 2000. It specializes in products to complement traditional genealogical research, and has a particular interest in Jewish genealogy, an aspect that has been discussed in: Nadia Abu El-Haj, The Genealogical Science: The Search for Jewish Origins and the Politics of Epistemology (Chicago and London: University of Chicago Press, 2012), 151–73. Today the company processes DNA admixture and uniparental analyses for various companies around the world, including the prominent Israeli genealogy company MyHeritage.

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John Novembre et al., “Genes Mirror Geography within Europe,” Nature 456 (2008): 98.

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Currently, only a subset of this database is used by the AncestryDNA test; the analysis also draws on the publicly available HGDP-CEPH panel, which includes 1050 individuals from 52 world populations, as well as samples donated by AncestryDNA members with known pedigrees. Catherine A. Ball et al., “Ethnicity Estimate White Paper” (AncestryDNA, October 30, 2013).

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The Church of Jesus Christ of Latter-day Saints (commonly known as the LDS Church or Mormon Church) has a keen theological interest in genealogical research, and has been involved in long-standing projects to collect and digitize genealogical data from around the world. Acolytes of the Church are expected to do “temple work” that involves tracing one’s ancestors in order to offer them the chance of salvation (see for example Fenella Cannell, “The Christianity of Anthropology,” Journal of the Royal Anthropological Institute 11 (2005): 335–56). The history of the SMGF collection and its acquisition by AncestryDNA is discussed further in Abel, Permanent Markers, 89–93.

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Pier Giorgio Solinas, Ancestry: Parentele elettroniche e lignaggi genetici (Florence: editpress, 2015), 70–71.

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Ball et al., “Ethnicity Estimate White Paper.”

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SNPs (pronounced “snips”) are base pairs of DNA that have been found to vary between individuals and populations, and are therefore regarded as ancestry informative.

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For a more in-depth discussion of the AncestryDNA “genetic ethnicity” test methodology, see Abel, Permanent Markers, 93–98.

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Some of the earliest DNA ancestry testing companies were aimed at helping African Americans recover their ancestors’ ethnic identities prior to slavery. See for instance, Alondra Nelson, The Social Life of DNA: Race, Reparations, and Reconciliation after the Genome (Boston, MA: Beacon Press, 2016); Sarah Abel and Marcela Sandoval-Velasco, “Crossing Disciplinary Lines: Reconciling Social and Genomic Perspectives on the Histories and Legacies of the Transatlantic Trade in Enslaved Africans,” New Genetics and Society 35, no. 2 (2016): 149–85.

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AncestryDNA no longer visualizes its “ethnicity” results in terms of continental groups; instead, test-takers currently receive a list of their composite “ethnicities,” ordered from highest to lowest percentage proportion.

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Peter Wade, Degrees of Mixture, Degrees of Freedom. Genomics, Multiculturalism, and Race in Latin America (Durham and London: Duke University Press, 2017), 17.

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Abel, “A la recherche des identités transatlantiques”; Abel, Permanent Markers, 95; 101–104.

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Ball et al., “Ethnicity Estimate White Paper.”

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Nelson, “Bio Science.”

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Jean-Luc Bonniol, “Penser et gérer l’hérédité des caractères discriminants dans les sociétés esclavagistes et post-esclavagistes,” Rives Nord-Méditerranéennes 24 (2006): 23–34; Wade, Degrees of Mixture, Degrees of Freedom, 2–3; Shay-Akil McLean, “Isolation by Distance and the Problem of the Twenty-First Century,” Human Biology 91, no. 2 (2019): 1–13; Abel, Permanent Markers, 10–12.

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Ricardo Ventura Santos and Marcos Chor Maio, “Anthropology, Race, and the Dilemmas of Identity in the Age of Genomics,” História, Ciências, Saúde – Manguinhos 12, no. 2 (2005): 1–22; Nelson, “Bio Science”; Noah Tamarkin, “Genetic Diaspora: Producing Knowledge of Genes and Jews in Rural South Africa,” Cultural Anthropology 29, no. 3 (2014): 552–74.

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See for instance Alondra Nelson and Jeong Won Hwang, “Roots and Revelation: Genetic Ancestry Testing and the YouTube Generation,” in Race After the Internet, ed. Lisa Nakamura and Peter A. Chow-White (New York & Abingdon: Routledge, 2012), 271–90.

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Abel, Permanent Markers.

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Myriam Cottias, La Question noire. Histoire d’une construction coloniale (Paris: Bayard, 2007).

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See “Racial Integrity Laws (1924-1930)” on the Encyclopedia, published February 17, 2009, last modified November 4, 2015, accessed May 14, 2020.

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Blay, “White Supremacist Would Be Black...”; Yaba Blay, (1)ne Drop: Shifting the Lens on Race (Philadelphia, PA: BLACKprint Press, 2013).

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Abu El-Haj, The Genealogical Science; Roth and Ivemark, “Genetic Options”; Abel, Permanent Markers, 114–46.

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In their 2018 study of the incorporation of genetic data into racial and ethnic identities among Americans of different racial backgrounds, Roth and Ivemark report some cases of White Americans incorporating a different racial identity after being attributed proportions of Native American or African DNA ancestry. However, the authors note that several of these test-takers kept this shift in identity private, as they were unsure whether or not their identity claims would be accepted by others, notably the communities to which they claimed affiliation. See also: Natasha Golbeck and Wendy D. Roth, “Aboriginal Claims: DNA Ancestry Testing and Changing Concepts of Indigeneity,” in Biomapping Indigenous Peoples: Towards an Understanding of the Issues, ed. Susanne Berthier-Foglar, Sheila Collingwood-Whittick, and Sandrine Tolazzi (Amsterdam: Rodopi, 2012), 415–32.

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In this respect, my research echoes the findings of Ricardo Ventura Santos et al., “Color, Race, and Genomic Ancestry in Brazil: Dialogues between Anthropology and Genetics,” Current Anthropology 50, no. 6 (2009): 787–819.

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Sarah Abel, “Rethinking the ‘Prejudice of Mark’: Concepts of Race, Ancestry, and Genetics among Brazilian DNA Test-Takers,” ODEERE 5, no. 10 (2020): 186–221,; Abel, Permanent Markers, 119–28.

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Thomas E. Skidmore, Black into White: Race and Nationality in Brazilian Thought, Paperback edition (Durham and London: Duke University Press, 1993); France Winddance Twine, Racism in a Racial Democracy: The Maintenance of White Supremacy in Brazil (New Brunswick, NJ: Rutgers University Press, 1998).

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Cobb, “Craig Cobb’s Ancestry.Com DNA Results.” “Octaroon” is an archaic racial term used to describe an individual with one-eighth “Negro blood.”

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Panofsky and Donovan, “Genetic Ancestry Testing among White Nationalists.”

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Panofsky and Donovan, 667. Similar claims about the “ideological” nature of genetic ancestry studies that purport to show that race has no biological basis have been observed by Ricardo Ventura Santos and Marcos Chor Maio in their discussion of the European White supremacist website Legion Europa. See: Santos and Maio, “Anthropology, Race, and the Dilemmas of Identity in the Age of Genomics.”

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Panofsky and Donovan, “Genetic Ancestry Testing among White Nationalists,” 670.

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See also Stănescu, “‘White Power Milk’: Milk, Dietary Racism, and the ‘Alt-Right.’”

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Panofsky and Donovan, “Genetic Ancestry Testing among White Nationalists,” 672.

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Abel, Permanent Markers, 104–105; 161–63.

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Reardon and TallBear, “Your DNA Is Our History,” S234.

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TallBear, Native American DNA, 59; Elizabeth Watt and Emma Kowal, “What’s at Stake? Determining Indigeneity in the Era of DIY DNA,” New Genetics and Society, 2019, 9–10.

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Darryl Leroux, “‘We’ve Been Here for 2,000 Years’: White Settlers, Native American DNA and the Phenomenon of Indigenization,” Social Studies of Science 48, no. 1 (2018): 87.

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Arthur Kemp, Four Flags: The Indigenous People of Great Britain: DNA, History and the Right to Existence of the Native Inhabitants of the British Isles, Fourth, Kindle (United States: Ostara, 2012); Catherine J. Frieman and Daniela Hofmann, “Present Pasts in the Archaeology of Genetics, Identity, and Migration in Europe: A Critical Essay,” World Archaeology 51, no. 4 (2019): 528–45

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Catherine Nash, Genetic Geographies: The Trouble with Ancestry (Minneapolis & London: University of Minnesota Press, 2015), 174.

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Michael Kent, “The Importance of Being Uros: Indigenous Identity Politics in the Genomic Age,” Social Studies of Science 43, no. 4 (2013): 534–56; ann-elise lewallen, “‘Clamoring Blood’: The Materiality of Belonging in Modern Ainu Identity,” Critical Asian Studies 48, no. 1 (2016): 50–76; Paul Brodwin, “‘Bioethics in Action’ and Human Population Genetics Research,” Culture, Medicine and Psychiatry 29 (2005): 145–78.

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Michael Kent and Peter Wade, “Genetics against Race: Science, Politics and Affirmative Action in Brazil,” Social Studies of Science 45, no. 6 (2015): 816–38,; Abel, Permanent Markers, 31–31; 52–53.

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Elena Calvo-González and Ricardo Ventura Santos, “Problematizing Miscegenation: The Fact/Fiction of Race in Contemporary Brazil,” Journal of Anthropological Sciences 96 (2018): 247–54; Sarah Lempp, “With the Eyes of Society? Doing Race in Affirmative Action Practices in Brazil,” Citizenship Studies 23, no. 7 (2019): 703–19,

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Charles N. Rotimi, “Genetic Ancestry Tracing and the African Identity: A Double-Edged Sword?,” The American Journal of Human Genetics 86 (2003): 661–73.

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Jenny Reardon, “The Democratic, Anti-Racist Genome? Technoscience at the Limits of Liberalism,” Science as Culture 21, no. 1 (2012): 36.

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Panofsky and Donovan, “Genetic Ancestry Testing among White Nationalists,” 675–76.

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Wade, Degrees of Mixture, Degrees of Freedom; McLean, “Isolation by Distance and the Problem of the Twenty-First Century.”

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Carol C. Mukhopadhyay and Yolanda T. Moses, “Reestablishing ‘Race’ in Anthropological Discourse,” American Anthropologist 99, no. 3 (1997): 526.

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Nancy Leys Stepan, The Hour of Eugenics: Race, Gender, and Nation in Latin America (Ithaca and London: Cornell University Press, 1991); Mónica G. Moreno Figueroa, “Distributed Intensities: Whiteness, Mestizaje and the Logics of Mexican Racism,” Ethnicities 10, no. 3 (2010): 387–401,

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Panofsky and Donovan, “Genetic Ancestry Testing among White Nationalists,” 676.

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