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Race doesn’t exist, the mantra went. The DNA insidepeople with different complexions and hair textures is99.9 percent alike, so the notion of race had no mean-ing in science. At a National Human Genome ResearchInstitute (NHGRI) meeting five years ago, geneticistswere all nodding in agreement. Then sociologist TroyDuster pulled a forensics paper out of his briefcase. Itclaimed that criminologists could find out whether a

suspect was Caucasian, Afro-Caribbean or Asian Indi-an merely by analyzing three sections of DNA.

“It was chilling,” recalls Francis S. Collins, directorof the institute. He had not been aware of DNA se-quences that could identify race, and it shocked him thatthe information can be used to investigate crimes. “Itstopped the conversation in its tracks.”

In large part thanks to Duster, Collins and other ge-neticists have begun grappling with forensic, epidemio-logical and pharmacogenomic data that raise the ques-tion of race at the DNA level. The NHGRI now routine-ly includes experts from the social disciplines to assist inguiding research priorities and framing the results forthe public. “The complexities of the DNA sequence re-quire not just simplistic statements about similarities be-tween groups but a full appreciation of history, an-thropology, social science and politics,” Collins has re-alized. “Duster is a person that rather regularly getstapped on the shoulder and asked for help.”

The urbane 66-year-old Duster, who splits his timebetween appointments at the University of Californiaat Berkeley and New York University, examines howthe public absorbs news about genetics into existing be-liefs and how those perceptions also shape the use ofgenetic sequencing, DNA probes and other moleculartechniques.

Those techniques have revealed that race is minor atthe DNA level. The genetic differences between any tworandomly selected individuals in one socially recognizedpopulation account for 85 percent of the variation onemight find between people of separate populations. Putanother way, the genetic difference between two indi-viduals of the same race can be greater than those be-tween individuals of different races—table sugar maylook like salt, but it has more similarities with corn syrup.

But genetics cannot prove that race doesn’t exist,Duster explains. No amount of logic will erase the con-cept or destroy the disparities that arise from it, becausepeople use race to sort their social groupings and to de-

The Reality of RaceThere’s hardly any difference in the DNA of human races. That doesn’t mean, argues sociologist Troy Duster, that genomics research can ignore the concept By SALLY LEHRMAN

■ Grandson of Ida B. Wells-Barnett, newspaper publisher, muckraker andantilynching crusader.

■ “The King of Coolocity,” says Harry G. Levine of Queens College, CityUniversity of New York, because like a disciplined musician Dustercombines seriousness, virtuoso skill, grace, balance and a relaxedplayfulness in his work (he is a jazz aficionado).

■ Current worry: “It is almost inevitable that a research agenda will surfaceto try to find patterns of allele frequencies and then create computer-generated profiles of different types of criminals.”

TROY DUSTER: THINKING ABOUT GENES

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fine their social and economic interactions. Moreover, they doso in ways that have significant biological consequences. Dusterrecently helped to draft a 15-page statement for the AmericanSociological Association showing how race persists as a factor indisparities in health and other areas of life. “You cannot just getrid of the concept without doing tremendous damage to the epi-demiologic research done so far,” Duster says. African-Ameri-cans are three times as likely to die from heart disease, for ex-ample. “Blacks are redlined by banks, followed by departmentstore security, pulled over by the police. This can produce hy-pertension,” he points out. “It can give you a heart attack.”

A new approach, gene clustering, avoids race by dividing ac-cording to medically important markers,such as genes for the enzymes necessary tometabolize drugs. But society will verylikely re-create racial categories and rank-ings under the new terms, Duster predicts.And by failing to name the social context,this strategy gives base-pair differences un-due emphasis at the expense of environ-mental influences. Race is a social reality,Duster observes, and he warns that scienceitself is a social institution susceptible to es-sentialist perceptions of race.

Raised in poverty during the Great De-pression by a mother from an upper-classfamily, Duster, whose father died when hewas nine, grew up navigating betweenChicago’s tough streets and its privileged intellectual and civicparlors. He witnessed firsthand the complexities of social cat-egories and learned to “code-switch” from one to another,much as he capably moves among sociology, anthropology andgenetics now.

Duster started out as a journalist but quit in moral indigna-tion when chided for failing to interview a trapped subway mo-torman waiting for a leg amputation. He turned to sociologyand joined Berkeley in 1967, quickly developing a reputationfor thought-provoking work on drugs and social policy. In the1970s Duster was a familiar voice in National Institutes ofHealth committees reviewing grants for research on mentalhealth and drug abuse. While sitting on a panel for PresidentJimmy Carter’s Commission on Mental Health, he began tohear researchers speculate that drug addiction and mental illnesswere linked to genetic susceptibilities.

Duster found the conversations alarming. His book, Back-door to Eugenics, aimed to stimulate public debate by showinghow genetic-screening policies tended to reinforce the powerstructures already within society. Since then, he has pressed ge-neticists and molecular biologists to consider the social mean-ing that emerges from what they perceive as unbiased fact.

At first they resisted. As a member of the Ethical, Legal andSocial Implications Working Group advising the agencies on hu-

man genome research, Duster urged the NIH and the Depart-ment of Energy to challenge The Bell Curve, the 1994 best-sell-er that argued that race correlated with intelligence. Governmentofficials held up a response for eight months, convinced that thenonexistence of race at the genome level spoke for itself.

Duster, along with fellow committee member DorothyNelkin of New York University, highlighted the ways in whichcultural context influences the application of medical and be-havioral genetics. Now Collins is relying on Duster and othercollaborators, such as University of Wisconsin molecular biol-ogist Pilar Ossorio, to help explain why race must be acknowl-edged even if it is biologically inconsequential. “It’s a tightrope

between trying to rescue the importanceand meaning of research on race withoutgiving it a false reality,” Duster says.

Indeed, although he maintains thatrace is significant in genetics, Duster insistsit is misleading to reinscribe race as a de-finitive system to group people who sharegeographic origins and thus some genes.For one, concepts of race vary geographi-cally as well as historically. The ethnic sta-tus of South Asians, for example, haschanged over the past century in the U.S.and more often serves to define a politicaland cultural “other” than something bio-logical. In 1920 Oregon granted citizen-ship to Bhagat Singh Thind of India dur-

ing a ban on Asian immigration. But the U.S. Supreme Court dis-agreed, stating that even though Thind should be considered“Caucasian,” he still wasn’t “white.” (Thind, who had joinedthe U.S. Army during World War I, managed to stay in the coun-try, earn a Ph.D. and publish 15 books on metaphysics.)

Researchers have also advocated assessing health risks with-in ethnic groups based on inherited variations in just one DNAbase pair. But such single-nucleotide polymorphism (SNP) pro-files can be deceptive, Duster warns. Ethnic differences in drugmetabolism or response to tobacco exist, but they appear to beminimal and depend strongly on the environment. The empha-sis on DNA, he remarks, transforms health status into a biolog-ical inevitability, and it is tempting to use the same tools to pro-file criminality or intelligence at the genome level.

Specific variations in DNA can be linked to ancestral geo-graphic origins, but those differences only occasionally offer amedically important clue. They fail to define any essential char-acteristics of a whole group. Race, itself a fluid idea, is part ofthe environmental context of the genome, Duster suggests. “Raceis a relationship,” he says. “When you talk about race as a rela-tionship, it prevents anyone from giving it false meaning.”

Sally Lehrman is a medical technology and health policyjournalist based in San Francisco.

DNA PROFILES raise issues about race thatsociologists such as Troy Duster must ponder.

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