The intricate interplay between genetics and social identity in Latin America has sparked significant debate. While DNA analysis has been pivotal in debunking the concept of biological races, it has also been misappropriated to perpetuate existing racial stereotypes.

The revelation of DNA's structure in 1953 ignited a transformative journey in genetics. Over the decades, the duration and cost of sequencing a human genome plummeted from 13 years and $1 billion to just two days and $1,301. The allure of DNA quickly captivated society, making the gene a cultural symbol imbued with extraordinary implications.

Genetics undoubtedly offers numerous benefits. Medical genetics has expanded, with researchers striving to identify genetic factors that may contribute to prevalent health crises like obesity, diabetes, and heart disease. Advancements in forensic science have enhanced law enforcement's ability to solve crimes through improved identification techniques. Furthermore, genetics plays a vital role in humanitarian efforts, assisting in the identification of remains from disasters or conflicts. Additionally, genetic research has illuminated aspects of human history, tracing early migrations and interactions among our species and related groups, such as Neanderthals.

However, the genetic revolution has not solely yielded positive outcomes.

My interest in DNA technologies deepened during my anthropological research on racism and racial inequality in Latin America. Genome analysis has substantiated the argument that "race" lacks a biological foundation; while genetic differences exist among populations, these do not correspond to socially defined racial categories. In this sense, genetic science has contributed to dismantling the flawed notion of biologically distinct races. Unfortunately, genetic data has also been misused.

Despite its potential to challenge biological concepts of race, genetic ancestry testing has been employed to validate notions of racial difference, reinforcing racist ideologies. This form of testing aims to ascertain the percentage of an individual's genome derived from specific ancestries, such as "African" or "Western European." Throughout Latin America, I have observed genetics being misapplied to bolster racial stereotypes and promote ideas of racial purity, countering anti-discrimination initiatives. Thus, genetics operates as a double-edged sword.

My extensive research over thirty years in Colombia and my review of academic literature reveal that many Latin American commentators and political figures often portray their countries as relatively free from the racism that is perceived to plague the United States. They contend that democracy arises naturally from the region’s history of racial mixing, where European colonizers intermingled with enslaved Africans and Indigenous peoples, resulting in the emergence of "mestizos" — individuals of mixed biological and cultural heritage — as a prominent and recognized demographic.

As early as 1861, Colombian writer and politician José María Samper celebrated the notion that the "marvelous work of the mixture of races" would yield a wholly democratic society, embodying a blend of European, African, and Colombian influences. Similarly, in the 1920s, Mexican politician José Vasconcelos extolled the virtues of a "cosmic race," positioning Latin Americans as its torchbearers. Their mestizo identity granted them a "transcendental mission" to unify diverse ethnic groups and foster social equality.

In mid-20th century Brazil, the concept of a "racial democracy" was promoted as the prevailing ideology. However, this official narrative contrasted starkly with the lived experiences of Black, Indigenous, and mestizo individuals, who reported systemic discrimination and the persistence of white elitism. The media and intellectuals often portrayed racism and racial mixing as mutually exclusive, akin to oil and water.

Fast forward to 2000, when Brazilian geneticist Sérgio D.J. Pena and his team published a "molecular portrait of Brazil," presenting findings from DNA ancestry tests conducted on a Brazilian sample. The results revealed that even those who identified as white possessed substantial African and Indigenous ancestry in their mitochondrial DNA. The authors speculated that raising awareness of this genetic diversity might foster a more equitable society in the 21st century. This notion of mixture equating to peace had resurfaced, now fortified by personal DNA insights.

My investigations into genomic science across Brazil, Colombia, and Mexico, conducted alongside colleagues, uncovered that Pena and his co-authors advocated for the use of DNA data to address social issues, particularly racism. They argued that Brazil's mixed heritage exemplified the scientific consensus that coherent biological "races" are indefinable. In a 2006 publication, Pena asserted that society must embrace the "scientific fact" of the nonexistence of races, aligning with the ideal of a nonracial, "color-blind" society.

In Colombia and Mexico, geneticists tended to focus on medical and forensic applications of DNA, often steering clear of racial discussions. Nevertheless, they consistently affirmed that individuals across these countries—regardless of whether they identified as Black, Indigenous, or white—shared a genetic tapestry comprising African, Indigenous, and European ancestry. The assertion that "we are all mixed" became an almost universally accepted truth, leveraging science to support the vision of racially harmonious societies.

If genetics were exclusively employed to illustrate biological mixedness, dismantle racial barriers, and promote social cohesion, the outcomes would be commendable. Sadly, this is not the complete picture.

Despite a longstanding narrative of Latin America's mixed heritage fostering racial harmony, significant discord persists. Indigenous and Black communities have consistently challenged the portrayal of Latin America as an egalitarian paradise.

In early 19th-century Colombia, Black military officers voiced concerns over discrimination, as did Black-led newspapers in São Paulo, Brazil, during the 1920s and 1930s. Following UNESCO's launch of a research initiative in Brazil during the early 1950s aimed at verifying claims of racial harmony, empirical evidence began to substantiate the narratives of discrimination. For instance, in Brazil, Black individuals earn approximately half of what their white counterparts make, experience more than double the illiteracy rates, and face maternal mortality rates over 40 percent higher. One study indicated that 24 percent of the wage gap between Black and white men stemmed from racial bias.

Genetic testing contributes to the reinforcement of perceptions of racial difference, further entrenching racial inequality. While these tests often emphasize biological commonalities among individuals, they are equally wielded to accentuate the minor differences between groups identified as Black, Indigenous, mestizo, and white based on their average ancestries. This focus obscures the fact that all humans are approximately 99.9 percent genetically identical.

Highlighting biological differences has historically underpinned racist ideologies, and if contemporary genetics also underscores these distinctions, it risks perpetuating racism anew. The foundational principle of DNA ancestry testing—that an individual possesses a certain percentage of African, European, or Indigenous genetic ancestry—employs reference populations as benchmarks for these estimations. Yet, casual observers might mistakenly interpret these reference groups as "pure" representations, reviving the concept of biologically defined races that genetics has strived to discredit.

Moreover, the application of DNA data has permeated public discourse, often including individuals well-acquainted with genomic intricacies. Pena himself contributed to the heated debate in Brazil during the early 2000s regarding race-based affirmative action. This discourse revolved around university admission quotas for Black applicants, which critics deemed unjust and divisive. Pena argued that since races lack biological grounding, they should not inform affirmative action policies. He contended that the legal classification of "Black" was devoid of a biological basis. Proponents of quotas countered that the term "Black" was not intended as a genetic category.

The crux of the quotas aimed to rectify discrimination faced by those perceived as Black by those controlling valuable resources and opportunities; the discriminators were indifferent to genetics. Black activist Frei David dos Santos pointedly remarked that police searches rarely consider an individual's genetic ancestry before discrimination occurs.

Other instances in Brazil illustrate the misuse of genetics to challenge race-based affirmative action. In 2007, BBC Brazil conducted DNA ancestry tests on nine public figures to explore their "Afro-Brazilian roots." Notably, the samba singer Neguinho da Beija-Flor, regarded as an Afro-Brazilian icon, was found to possess 67 percent European ancestry. While he dismissed the findings as inconsequential to how he and others perceived his identity as unequivocally Black, this DNA result was widely publicized as evidence against a legitimate category of Black Brazilians entitled to public policies.

The rejection of biological race was weaponized against social movements aimed at addressing the well-documented disadvantages stemming from past and ongoing racism in Brazil.

DNA has also served to both reinforce and contest social identities. In Colombia, certain geneticists focused their research on Medellín, the capital of Antioquia, a province associated with the paisas—a regional group often stereotyped for their entrepreneurial spirit and perceived whiteness.

In their scientific publications, researchers demonstrated that individuals from Medellín and surrounding towns exhibited significant Amerindian ancestry in their mitochondrial DNA and notable European ancestry in their autosomal DNA. This genetic pattern is common among many Latin Americans, reflecting the legacy of violent historical encounters between European men and Indigenous and African women.

Interestingly, the study categorized the paisas as a "genetic isolate," a term denoting populations with limited genetic exchange since the arrival of conquistadors until the mid-20th century. While this could apply to most Latin American populations, with the exception of Argentina and Brazil—which received millions of European immigrants during that period—the findings were co-opted to reinforce the notion of the paisas as unique, bolstering their perceived whiteness. A major radio network sensationalized the research, declaring, "Confirmed: Antioquia Is a So-called Genetic Isolate; The Antioqueños Are 80 Percent European."

The application of genetic tests can yield other troubling implications. In Mexico, government investment in genomic research has surpassed that in Brazil and Colombia. The National Institute for Genomic Medicine's flagship project aimed to create a genetic diversity map of Mexico, revealing, as expected, that most Mexicans are genetically mixed, with regional variations reflecting their historical ancestry.

Subsequent projects investigated potential genetic factors behind rising obesity and diabetes rates in Mexico, attributing some variants to Indigenous ancestors. This focus on genetic explanations has faced scrutiny, as diet and lifestyle are recognized as critical contributors to these health issues. Furthermore, these studies attempt to impose a biological distinction between mestizos and Indigenous peoples, despite many Indigenous individuals also having European ancestry. This perpetuates social divisions traditionally marked by cultural traits, assigning a negative genetic connotation to Indigenous identity, which is burdened with risk-laden genes. As seen in Brazil and Colombia, DNA has intertwined with social hierarchies, sometimes reinforcing racial disparities.

Genetic science has undeniably advanced human welfare and holds immense potential for further contributions. However, there are legitimate concerns regarding the potential misuse of DNA for eugenics-style selection and the criminalization of certain populations through biased DNA databases. My research in Latin America underscores the risks associated with how DNA data is interpreted in the context of racial differences. The persistent danger lies in using genetics to define racial identities—such as Indigenous, Black, and mestizo—shaped by colonial and postcolonial hierarchies.

While significant genetic differences exist among humans, impacting individual health outcomes, geneticists continue to debate how these differences manifest in population patterns. There is considerable contention regarding whether these patterns correspond with traditional notions of "races."

It is crucial to remember that human categorization is largely influenced by social and cultural factors. People often mistakenly perceive their classifications as rooted in nature, which can be exploited to justify discrimination and inequity. Geneticists and the general public must remain vigilant about the harmful transitions between culture and biology, both in genetic research practices and in the broader societal application of genetic data.

Peter Wade is a professor of social anthropology at the University of Manchester.

The capitalization of Black is intentional at the author’s request. SAPIENS’ style is to lowercase black (and white), per the Associated Press Stylebook and the National Association of Black Journalists’ style guide.