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1266 VOLUME 10 | NUMBER 12 | DECEMBER 2004 NATURE MEDICINE

Scientists divided on relevance of race in medical researchA new drug that promises to selectively treatheart failure in African-Americans is up forapproval from the US Food and DrugAdministration. But the controversy that surrounds BiDil, which would be the first drugmarketed to a specific racial group, illustratesthat, among scientists, there is little consensuson the usefulness of race in genetic studies.

BiDil appears to be ineffective in whites, butin blacks, researchers reported that the drugreduces mortality by 43% (N. Engl. J. Med. 351,2049–2057; 2004). But the problem with thisapproach is that it seems to confirm a geneticdifference between races where there may benone, says David B. Goldstein, a geneticist atUniversity College London.

Researchers who receive federal funds arerequired to include people of varying self-reported racial and ethnic groups in their stud-ies. But race or ethnicity is “a blurry proxy” thatreflects environmental and cultural, as well asgenetic, differences, says Francis Collins,director of the US National Human GenomeResearch Institute in Bethesda. About 99.9% ofthe genome is identical from person to personand most variation occurs within racial andethnic groups, not between them. Nonetheless,some differences in health have been found toalign with self-reported race.

Most scientists agree that race—or, perhaps,a sociodemographic group—is often an impor-tant surrogate for environmental, cultural andeven genetic factors underlying disease predis-position and outcomes. “Race isn’t the endingpoint, it’s the starting point,” says Neil Risch,professor of genetics at Stanford University.

For both social and scientific reasons, how-ever, race is a troublesome word, saysShomarka O.Y. Keita, senior research associateat Howard University’s National HumanGenome Center. Socially, Keita notes, the termis associated with racism; scientifically, it hasbeen used to describe ‘subspecies’—a geneticdivergence far too broad to describe the minorgenetic variations found between people.“Sociodemographic groups of Americans canand should be studied,” Keita says, “but they are not subspecies or isolated breeding populations; they are not races.”

Still, it doesn’t make sense to get rid of theterm race because, like sex and age, race can pro-vide valuable information, some researchers say.Because scientists often find what they look for,however, it is important to track socioeconomicstatus, environmental exposures, housing andaccess to care even in genetic studies.

Alexandra Shields, associate professor at theHealth Policy Institute at Georgetown

University, urges caution in using race as a variable.“There’s a danger in looking for causalexplanations from genes when the differencesare almost certainly more powerfully related toenvironmental factors,” says Shields. In theJanuary issue of the American Psychologist, sheand her colleagues will argue that although racemay be appropriate to use during recruitment,“self-identified race should no longer be used ingenetics analyses.” Instead, geneticists shouldtest people to genetically determine the conti-nental ancestry of their grandparents, she says.

Keita also suggests replacing racial-ethniccategories with ancestry and collecting infor-mation on where people live, early life history

and environment. For instance, environmentalexposures that have not yet been identifiedmight appear genetic. Socioeconomic differences between mothers in differentgroups might also result in different fetal environments, which might affect adult health.

Some research journals request thatresearchers specify ancestral and environ-mental information so that the data can begrouped flexibly for medical geneticists,epidemiologists and biological anthro-pologists. “We can’t abandon race because itmight be our only clue to a problem,” Collinssays. “But it’s not enough on its own.”

Damaris Christensen, Washington, DC

UK criticized for embryo screening decisionThe UK’s Human Fertilisation andEmbryology Authority (HFEA) has comeunder fire for allowing, for the first time inBritain, genetic screening of embryos for adisease that will not affect the child at birth.Critics say the agency made the ethicallycharged decision without input from experts,paving the way for indiscriminate screening ofembryos for adult-onset diseases.

Preimplantation genetic diagnosis, or PGD,is generally used to screen for chromosomalabnormalities and diseases such as cysticfibrosis. In some countries, such as Australiaand Jordan, it has also been used for genderselection.

HFEA granted the license on 1 Novemberto the assisted-reproduction unit ofUniversity College Hospital in London toscreen for familial adenomatous polyposis,which can lead to colon cancer in earlyadulthood. Couples with the geneticcondition have a 50% chance of passing iton to their children. An anonymouscommittee of five people made the decisionto grant the license.

The HFEA says that it consulted experts onPGD for various diseases, including cancers,in 2001, says Vishnee Sauntoo, a spokespersonfor the agency. By law, the HFEA is allowed togrant licenses based on a decision made by acommittee of five people, Sauntoo notes.

"If it is acceptable to do prenatal diagnosisand terminate an affected pregnancy thensurely it is okay to do PGD and select a healthyembryo before implantation,”says JoyceHarper, deputy director of University CollegeLondon’s PGD center. PGD for the BRCA1and BRCA2 breast cancer genes, is offered inother European countries, Harper notes.

But many experts have criticized theagency’s move.“This is an ethically importantdecision which should have been discussedproperly with scientists, physicians and thepublic,”says Mohammed Taranissi, director ofthe Assisted Reproduction and GynaecologyCentre in London.

The UK government’s Human GeneticsCommission is reviewing guidelines forreproductive decision making, notes SueMayer, director of the lobby group GeneWatchUK. By granting the license,“HFEA haveeffectively set the precedent before thatprocess has been ended,”Mayer says.

Comment on Reproductive Ethics (CORE),a pro-life group, is considering legal actionagainst HEFA for making an “undemocratic”decision without consulting the public orParliament, says Josephine Quintavalle,CORE’s director. CORE is also challenging theHFEA for granting a license for 'savior' siblingPGD. That case is scheduled for March 2005.

Xavier Bosch, Barcelona

How important is race? In medicine, the issues are not black and white, scientists say.

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