Genetic Drift

The study of human genes has sparked a resurgence of debate about the true nature of race.

By Ziba Kashef Oct 03, 2007

Ever since scientists discovered “the secret of life” embedded in our DNA a half century ago, the study of human genes has sparked debate about the nature of race. The question seemed to be settled in the early 1970s when biologist Richard Lewontin compared variations in genes within and among different population groups. His conclusion, that most human genetic variation did not fall along racial lines, was widely accepted. At the molecular level, human beings are more alike than different. Repeat experiments confirmed this finding, and many experts embraced the knowledge that the racial categories that have long divided people and justified racist oppression represented social and political beliefs rather than biological truths. 

    But the notion that race is real as a biological fact did not die. Even after research teams who identified and sequenced all 20,000-25,000 genes as part of the historic Human Genome Project declared in 2000 that race was not a valid scientific concept, the counterclaim resurfaced. Ironically, the more science has delved into the intricacies of our DNA, the more experts have diverged on the question of race. The dispute, which reverberates mostly in the pages of academic journals and in the halls of some of our most prestigious institutions, could have negative repercussions in the real world for communities of color. From criminal justice to medical research and genealogy, the lack of clarity on the true nature of race poses risks, including the risk that, as a society, we might start believing in essentialist notions of race again.

    While acknowledging that science is often used for positive purposes, including ones that benefit communities of color, social justice advocates must remain vigilant. All technologies, including new genetic technologies, develop in a political, economic and social context, says Patricia Berne of the Center for Genetics and Society, a public affairs nonprofit based in Oakland, California. “The broader political left has not really grappled with the ways these technologies affect our claim to resources, our claim to rights, and the well-being of our communities,” she notes. Before race is resurrected and redefined by biologists, geneticists and biotech firms, social justice advocates must grapple with the issues and add their voices to the debate.
    
FORENSICS
This spring, the New York Times published a startling article entitled “The DNA 200,” a brief piece with a collection of thumbnail-size photos of former inmates who had been released on the basis of DNA evidence. A quick survey of the images was compelling—most of the faces were Black and brown men who had spent an average of 12 years behind bars for crimes they had not committed. Each face and each exonerated individual represented a victory for the Innocence Project, an 18-year-old legal advocacy group that  works to reopen old cases and change lives with the help of DNA evidence. For these men, DNA analysis helped prove, without a shadow of doubt, that genetic material uncovered at a crime scene did not match their own. Science was an instrument of justice.

    But just as easily, DNA can be turned into a high-tech tool for racial profiling, although on shakier scientific grounds. It led to the 2004 conviction of an African American suspected of multiple serial murders in Baton Rouge, Louisiana. Initially, police sought a white suspect, based on eyewitness testimony and the assumption that most serial killers are Caucasian. But the case took a turn when a technology firm, DNA Print Genomics, offered to analyze the sample from the crime scene. Their test concluded that the suspect was “85 percent sub-Saharan African and 15 percent Native American” and therefore medium- to dark-skinned black, not white. It appeared to match a sample given to police voluntarily by Derrick Todd Lee, a man with a history of legal troubles. Lee’s conviction and death sentence were based in part on a method that critics say is at best a prediction of geographical ancestry—not a 100-percent certainty.

    The stockpiling of DNA samples from suspects and convicts has become the norm in many states. Even the liberal governor of New York, Eliot Spitzer, recently proposed expanding the DNA database there to include individuals convicted of misdemeanors such as minor drug violations and unlawful credit card use. Virginia also collects the DNA of nonviolent offenders, and Louisiana requires samples from those who are simply arrested for a felony. Previously, DNA had been collected only from those found guilty of the worst crimes. Spitzer’s proposal is supposed to make it easier for prosecutors to lock up more criminals and for the wrongly accused to prove their innocence. But given the racially biased arrest and conviction patterns of New York and other states across the country, the consequences are likely to disadvantage people of color.

As databases mushroom, the development of genetic racial profiles may be the next wave in law enforcement. DNAPrint claims the ability to use DNA to “predict” physical features such as skin and eye color, adding more and more detail to a genetic sketch. Their web site boasts 100 percent accuracy in blind, company-administered tests. But one critic pointed out that since the test that identified the Baton Rouge killer estimated the percentage of ancestry from four groups that mostly include dark-skinned individuals (sub-Saharan Africans, East Asians, Indo-Europeans, Native Americans), any prediction would inevitably fall into one or more of those ethnic groups. The company provides a separate screening test for additional groups, such as Northwestern and Southeastern Europeans, Middle Eastern and South Asian, but less commonly.

Such racialized forensics presents multiple problems for people of color. It blurs the line between DNA tests that can definitively rule out suspects (as in the Innocence Project) and less certain analyses that “predict” or state the probability of a match. It gives scientific legitimacy to the widespread but still controversial notion that certain genetic differences, or markers, correlate precisely with geographic regions and modern racial categories. Further, it makes acceptable manhunts for “ancestry informative markers,” a euphemism for racial identifiers in genes despite the many pitfalls of old-fashioned racial profiling. Worse still, it creates a market for a growing list of genetic services that may, at best, be good guesses but not definitive.

Critics fear that such questionable science in criminal justice will inevitably lead to searches for gene markers for criminal behavior. If criminologists start with a database that is disproportionately Black and Latino because of police practices that target those communities, any computer-generated findings will be skewed. “What you’re dealing with is a population in the database which is distorted,” says Troy Duster, a sociologist and chancellor’s professor at UC Berkeley. “So if someone wants to do this kind of research, they’ll look for genetic markers. What they’ll find, of course, are certain markers. Tell the program to find markers and you can find markers in DNA that may be more or less likely to appear in populations A, B or C. But it will be a huge mistake to conclude that because you have those markers you’ve explained crime.”

The ever-expanding databases give law enforcement a powerful, high-tech tool. With each DNA sample, government seizes personal biographical information, stripping citizens of their privacy rights. Since each sample offers clues not only about individuals but their relatives as well, entire families are open to scrutiny. In some cases, once a DNA sample is taken it is not destroyed or returned but stored indefinitely, unless the law in a particular state stipulates otherwise.

MEDICAL RESEARCH
Genetic science is similarly double-edged in the realm of health research. As scientists were busy mapping the human genome in the early ‘90s, for the first time the government moved to mandate that all federally funded biomedical and behavioral research include members of historically excluded groups: minorities and women. After decades of research on mostly white, male subjects, this development—pushed both by Black politicians and women scientists—was generally hailed as an advancement. Documenting health disparities is indeed an imperative, given the much higher rates of disease and mortality from disease among ethnic minority groups in the United States.

    But the mandate had at least a few notable detractors. As it was to take effect, a handful of African American scientists voiced opposition, according to Duana Fullwiley of Harvard, who recently published “The Molecularization of Race” in the journal Science as Culture. Dissenter Otis Brawley, formerly at the National Cancer Institute, wrote: “The legislation’s emphasis on potential racial differences fosters the racism that its creators want to abrogate by establishing government-sponsored research on the basis of the belief that there are significant biological differences among the races.” But by the time Brawley and others registered their complaint, the train had already left the station. The use of racial categories in applications for research funding and reporting of results had become the accepted norm. 

Paradoxically, as the Human Genome Project discredited the use of race in science, the pharmaceutical industry moved in the opposite direction, according to Fullwiley. Instead of focusing on the 99.9 percent overlap in all human genes, the Pharmacogenetics Research Network, a government funded follow-up to the Genome Project, honed in on the 0.01 percent difference as a source of the new discoveries and therapies. And several scientists and researchers sought further funding for investigations into possible genetic causes for racial disparities in disease and drug responses.

Their faulty reasoning, however, is illustrated by the controversial race drug BiDil. Developed to address the greater mortality from heart failure among African Americans, the drug has been met with both celebration and skepticism. While it is true that Blacks ages 45 to 64 are more than twice as likely to die from heart failure than whites, Duster points out that the disparity narrows after age 65. The disparity may have less to do with biology and race than other documented factors in heart disease, such as diet, stress and lifestyle. Evidence outside of the U.S. also undermines the rationale for a race-based approach to the condition. Citing the data of epidemiologist Richard S. Cooper, who compared hypertension rates worldwide, Duster explains, “Germany has the highest rate of hypertension, and Nigeria has the lowest rate. It doesn’t take a Ph.D. in epidemiology to figure out what might be the issue there. It can’t be race and genetics.”

    Scientists do, of course, acknowledge the influence of environment and lifestyle on disease and disparities. The laser-like focus on, and blind faith in, genes as the source of understanding and treating disease has been tempered by technical challenges and other trends in medicine. But the damage to our society’s understanding of race may be done. As federal dollars continue to flow to research on the genetic basis for certain racial disparities—in diabetes, asthma, alcoholism and other conditions—race as a biological fact becomes more solidified in public consciousness, and the socioeconomic factors in disease get obscured. “It takes the issue in a crude way and focuses it on what’s going on inside the body,” says Duster. “[But] if you say, well, maybe there is a complex interaction between environment and disease, then the answer is going to be primarily outside the body.”

 Even if more race-specific medicines and therapies are developed from pharmacogenetic research, it’s unclear whether those treatments will actually alleviate disparities. Most diseases that disproportionately afflict African Americans and other ethnic groups—heart disease, cancer, diabetes—are not caused primarily by single genes or even clusters of genes. Even in cases where illness is linked to specific genes, like sickle cell disease, no miracle cures are forthcoming. With less access to health insurance and health care, people of color may not have access to new treatments or the personalized medicine that remains the goal of many genetic scientists.

GENEALOGY
Another area where genetics and race collide is genealogy. Curiosity about our origins has motivated countless Americans, including people of color, to have their DNA tested and compared with samples from around the world. Dozens of companies have met the demand with genealogy services that charge a fee for collecting samples, analyzing results and providing answers to questions about family history. In a famous case, the descendants of Sally Hemings, who as a slave had a relationship and son with Thomas Jefferson, used DNA testing to prove they were indeed related to the Founding Father, despite denials from Jefferson’s white descendants. More recently, media mogul Oprah Winfrey declared that a DNA test had shown that she was Zulu.

    But Winfrey’s case is an example of the false confidence many people place in the results of ancestry testing. DNA analysis of ancestry typically traces DNA along one of two lines—the paternal Y chromosome or maternal mitochondrial line. It can give people accurate information about their father and father’s father, or mother’s mother and so on (thus conferring accuracy to the Hemings/Jefferson test). But each individual’s family tree is much greater than one line. If you go back four generations, you have 16 ancestors—but the testing only provides details about one of them, capturing only a partial picture of lineage. Further, while Winfrey’s genetic sample appeared to match the DNA of others identified as Zulu, the term describes a cultural and linguistic group that coalesced sometime after slaves were taken primarily from West Africa to the Americas.

    The science gets even more questionable when researchers and biotech firms attempt to draw conclusions about the ancient ancestry of entire groups. Two years ago, the National Geographic Society and IBM announced an ambitious project to collect more than 100,000 samples of DNA from indigenous people worldwide. The plan, known as the Genographic Project, was to use the DNA, collected from cheek swabs, to study ancient migration patterns and learn more about where different populations originated. With $55 million in funding and 10 centers based globally, the project was poised to amass, as its web site states, the largest DNA database of its kind in the world.

    But the project’s methodology is no more precise than other ancestry testing services. It also uses proprietary computer programs to trace either paternal or maternal lines, leaving a majority of an individual’s ancestors out of the analysis. It assumes that certain indigenous populations have been isolated and their genes not complicated by migration and mixing with other populations—an assumption many Native Americans challenge. The project also conflates geography with ancestry and culture, which can be easily interpreted as race.

From its inception, the project has met with resistance from several indigenous groups. Though some have participated, most North American tribes and nations have declined. Given the history of scientific racism, indigenous people are wary of the project’s intentions and consequences. While scientists stand to gain knowledge, and career advancement, from research on indigenous people, those populations potentially have a lot to lose. For example, the project poses questions about the aboriginal inhabitants of various regions and countries, and if it were to conclude that groups in Alaska came from Asia or elsewhere, the research could be used to undermine indigenous claims to land and other rights. “Governments have a long history of trying to divest indigenous peoples of their land rights and undermine their cultural integrity,” says Debra Harry, executive director of the Indigenous People’s Council on Biocolonialism, which opposes the project.

The terms “ancestry” and “genetic diversity” have emerged as alternative ways to describe the differences we know as race. But they may be no more accurate in expressing human genetic variation than traditional racial categories are. Genetic markers attributed to one group or region of the world can be found in others. Whether scientists discuss the variations in terms of geography or ancestry, the impact will be the same: resurrecting race and racial differences as concrete biological facts, encoded deep within our DNA, and confirmed by science.   

Ziba Kashef writes frequently about health and race issues. Her work has appeared in Real Health, NMA Healthy Living, Essence and other publications.

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