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Sandra Soo-Jin Lee, Joanna
Mountain, and Barbara A. Koenig
excerpted from: Sandra Soo-Jin Lee, Joanna Mountain and Barbara A. Koenig, The Meanings of "Race" in the New
Genomics: Implications for Health Disparities Research, 1 Yale Journal
of Health Policy, Law & Ethics 33-68 , 53-59 (Spring 2001)(102
Footnotes Omitted)
Historically, race, genetics, and disease have been inextricably
linked, producing a calculus of risk that implicates race with relative
health status. Racialized groups have been associated with particular
diseases. Sometimes these associations are accurate and sometimes they
reflect underlying social prejudice. It is against this backdrop that
investigations into health inequalities in the United States play out.
Troy Duster, a sociologist who has examined these associations, has
identified this process as the "prism of heritability" in
which disease is uncritically linked to individuals because of racial
assignment and categorically disassociated from other populations. He
cautions that race-based etiological theories may become hegemonic,
effectively eliminating explanations of illness that take account of
environmental or behavior factors associated with social class.
Melbourne Tapper has studied this process with respect to the
identification and management of sickle cell anemia in colonial Africa.
Tapper reveals that the political project of colonialism was further
justified by the dominant discourse on race that identified sickle cell
anemia as a "black disease" and contributed to a definition of
"whiteness" that was predicated on the notion of
invulnerability and health. Similarly, in the United States, prejudicial
attitudes toward African Americans and immigrants from the Mediterranean
region fueled racial rhetoric around sickle cell anemia and thalassemia.
In the twentieth century, the association of race with disease was
utilized by those who were politically opposed to miscegenation and
immigration of people from southern Europe.
Given this history, particular caution must be employed when using
the race concept in health-related research. Some have argued that the
concept should be abandoned, based on the overwhelming scientific
evidence that human races do not exist. Others argue for retaining the
term, but limiting its application to the social, as opposed to the
biological, realm. Recently, the American Anthropological Association,
the official professional organization of physical, biological, social,
and cultural anthropologists and archeologists in the United States,
released a statement emphasizing the social and historical construction
of race. Reflecting a general consensus among social scientists,
physical and biological scientists and other scholars, the statement
contended that race could not be considered a valid biological
classification:
The "racial" worldview was invented to assign some groups
to perpetual low status, while others were permitted access to
privilege, power, and wealth. The tragedy in the U.S. has been that the
policies and practices stemming from this worldview succeeded all too
well in constructing unequal populations among Europeans, Native
Americans, and peoples of African descent. Given what we know about the
capacity of normal humans to achieve and function within any culture, we
conclude that present-day inequalities between so-called
"racial" groups are not consequences of their biological
inheritance but products of historical and contemporary social,
economic, educational, and political circumstances.
Despite such proclamations, race continues to be used erroneously,
even harmfully, as a scientific variable, particularly in biomedical
research designed to explain health behavior. Its use is ubiquitous;
from 1910 to 1990, race was used in 64% of articles appearing in the
American Journal of Epidemiology. One author suggests that historians
will find our current terminology to be inherently racist, rather than
scientifically useful. A review of biomedical literature claiming links
between race and disease reveals that researchers rarely describe their
racial and ethnic measurement or classification methods. In a review of
articles published in Health Services Research, Williams noted,
"Terms used for race are seldom defined and race is frequently
employed in a routine and uncritical manner to represent ill-defined
social and cultural factors." Lack of precision--näively
conflating biology and culture--makes it impossible to tease out the
causes of health disparities between economically disadvantaged
racialized populations and more privileged groups.
The lack of consistency in the use of terminology for concepts of
race, ethnicity, ancestry, and culture is manifest in the wide variance
in terms used to identify individual and group identities. Terms such as
white, Caucasian, Anglo, and European are routinely used interchangeably
to refer to certain groups; whereas black, colored, Negro, and African
American are used to refer to comparison groups. And white-black
comparisons are straightforward in contrast to the confused use of terms
like Hispanic and Asian. Fundamental ambiguity in the concept of race
obscures the role that genetic variation plays in our current
understanding of disease. Socially defined notions of race are treated
as legitimate biological variables; race itself is often used as a proxy
for disease risk. Epidemiological studies employ race as shorthand for
social and environmental factors that are associated with particular
racialized groups. When treated in this way, race is understood to have
some contributory effect to particular conditions and diseases, but in a
very imprecise way. For example, reports that black smokers are ten
times more likely to develop helicobactor pylori infection--a cause of
duodenal ulcers--than white smokers, treats skin color as an independent
variable, and thus circumvents an explicit engagement with the complex
interaction of social, environmental, and perhaps, biological factors
that may have produced the statistically significant findings.
Research utilizing race serves to "naturalize" the
boundaries dividing human populations, making it appear that the
differences found reflect laws of nature. In fact, the use of race and
ethnicity in biomedical research is problematic because it is caught in
a tautology, both informed by, and reproducing, "racialized
truths." We assume that racial differences exist, and then proceed
to find them. While the scientific validity of racial distinctions
between human populations has long since been disputed, the cultural
logic of stratifying populations by race/ethnicity exerts a powerful
pull--it is a highly ritualized scientific practice enshrined in law and
government regulation.
A. Race, Smoking, and Nicotine Metabolism
Recent research on smoking and nicotine metabolism illustrates the
implications of the reification of the race concept in health research.
The use of tobacco is singled out as a leading health indicator in the
Healthy People 2010 vision statement. According to the report,
adolescent rates of cigarette smoking have increased in the 1990s among
white, African-American, and Hispanic high school students after years
of declining rates during the 1970s and 1980s. A central goal of the
Healthy People 2010 mission is to decrease the rate of tobacco use
through prevention programs and to focus research on treatment programs
for existing smokers.
Epidemiological and behavioral research on cigarette smoking has
clearly identified sociodemographic variation in smoking rates.
"Race" is highlighted as a significant predictor of smoking
behavior, yet its exact salience is difficult to tease out. Studies
indicate that although a larger proportion of blacks than whites smoke,
several differences in tobacco use exist between these groups. Blacks
consume fewer cigarettes and begin smoking later in life than whites.
Blacks smoke cigarettes higher in tar and nicotine and are specifically
targeted by the tobacco industry as potential consumers. Smoking among
African Americans has been associated with a higher incidence of lung
cancer, cardiovascular disease, low birth weight, and infant mortality.
Research on a genetic basis for differences between African Americans
and non-Hispanic European Caucasians has focused on differences in the
metabolism of tobacco. The logic of such studies is founded on the
notion that racial groups may have distinct genetic characteristics that
result in different biochemical processes such as variations in nicotine
metabolism. Recently it has been reported that racial and ethnic
differences may exist in the serum cotinine levels of cigarette smokers.
Levels of cotinine, a metabolite of nicotine, indicate relative exposure
to tobacco smoke. In this study, sponsored by the National Center for
Chronic Disease Prevention and Health Promotion, non-Hispanic black
smokers had significantly higher levels of serum cotinine than either
white or Mexican-American smokers despite reporting to have smoked the
same number of cigarettes a day. The study concluded that these
differences may explain why blacks find it harder to quit and are more
likely to experience higher rates of lung cancer than white smokers. The
authors suggest that biological differences may account for the
differential health status of certain groups. Studies like this
contribute to a trajectory of research that links race and genetics to
disease. However, by assuming a tight link between nicotine metabolism
and race, researchers may overlook other biological or environmental
mechanisms that could explain the elevated cotinine. They also rule out
racism on the part of physicians as an explanation of excess cancer
deaths among blacks. A recent study found racial differences in referral
for potentially curative surgery among patients diagnosed with
early-stage lung cancer associated with smoking.
Research on the relative incidence of disease among racialized groups
reflects a paradigm of inquiry that presumes racial differences exist.
"Race biology," as described by Gary King, reflects current
sociopolitical beliefs, values, and agendas regarding racial differences
and is "predisposed to and rewarded for investigating 'inherent
differences' rather than commonality." Research findings--such as
differences in nicotine metabolism-- provide the promise of drug
therapies based on presumed genetic differences between racialized
groups. Such targeted medicines are a hallmark of the new genomic
medicine.
B. Race and Pharmacogenomics
The emergence of the field of pharmacogenomics is based on the
promise of individually tailored drugs; therapeutics will be tailored to
the unique genetic makeup of specific populations. Those more likely, or
less likely, to respond to a particular medicine, or those likely to
have a severe adverse event, will be identified through genomic
analysis. Pharmaceutical companies believe that such tests, and the
medicines based on them, will be an important feature of health care in
the future; intense and highly competitive research is underway.
Pharmacogenomics creates drugs for individuals by matching medicines
to patients' personal genetic codes. However, in practice, research
targets variation within pre-defined racialized groups, not individuals.
According to a recent article in the Washington Post, "[r]ace
influences which people are genetically predisposed to lack various
enzymes needed to break down medications. Without those enzymes, the
medication can have either a heightened or lessened effect." In
this case, race is identified as the independent variable that explains
the necessary presence or absence of a biochemical agent that aids the
metabolism of the drug. The use of the word "lack" redirects
focus from the limitations of synthetic pharmacopoeia to the biological
shortcomings associated with particular racialized groups. Who will be
defined as "normal?" Racial thinking, or the belief that race
is defined by biological differences between groups of individuals,
informs the search for genetically tailored therapeutics intended to
compensate for deviations from an unstated standard of genomic
normality.
Although the idea of individually tailored therapy is the goal, it
appears likely that products will actually be targeted according to
race. One can only speculate on the cultural impact of the
commercialization of drugs for racialized populations and the decision
by pharmaceutical companies to bring to market therapeutics created for
a certain group of consumers. The Food and Drug Administration (FDA)
recently approved a new glaucoma drug, Travatan, which is marketed as,
"the first glaucoma drug to demonstrate greater effectiveness in
black patients." Close reading of the FDA-approved package insert
discloses that "[i]t is not known at this time whether this
difference [in efficacy] is attributed to race or to heavily pigmented
irides." This turn toward a population-based approach to health
care product marketing raises the possibility that drug development will
build upon and strengthen current notions of racial difference. Health
disparities do exist; individuals who self-identify as black are more
likely to suffer from glaucoma-related blindness. But will medicines
targeted by race alleviate those differences in health outcomes or
disguise other explanations of disparities, such as lack of access to
routine preventive eye care? The danger is that more and more diseases
will be "racialized," and at the same time, the idea that
racial differences exist and are inherent is reinforced. Careful policy
guidelines on the marketing of medicines (and other health care
products) to racially defined groups are needed. These guidelines must
pay attention to language in order to avoid the suggestion that
biologically distinct human races exist. One policy suggestion is to
insist on neutral words such as "ancestry" when discussing
population-level genetic variation, avoiding potentially misleading
terms.
Pharmacogenomics research is the study of the genetic basis for
differential drug responses between individuals. Identifying those
genetic differences depends upon access to research databases that
reflect a wide range of difference across the human population. Genetic
variations, called SNPs, provide the raw material for research. SNPs
occur at the rate of one in approximately 300 base pairs. The promise of
SNPs research is the discovery of genes involved in human disease, such
as asthma, diabetes, heart disease, schizophrenia, and cancer. (At the
molecular level, sickle cell anemia is the result of a variant SNP.)
SNPs are believed to play a major role in how humans respond to
environmental insults such as bacteria, viruses, toxins, and chemicals
(e.g. nicotine), including drugs and other therapies. The NIH, as well
as private companies, have set up databases including a
"representative" sample of human DNA. Because these databases
must reflect the human population, how researchers conceptualize the
racial or ethnic background of blood samples reveals a great deal about
existing taxonomies of race.
Initially, databases were set up reflecting known social categories
of difference. The Coriell Cell Repository, for example, includes cell
lines-- called "human variation panels"--from an amalgam of
people, including such conceptually distinct categories as African
American, Caribbean, Greek, Caucasian, Chinese, South American (Andes),
and Southwestern American Indian. Recognizing the issues we have
identified in this paper, the NIH took a very different tact in setting
up its "DNA Polymorphism Discovery Resource." Established in
1998, samples were collected from 450 male and female U.S. citizens,
apparently with the intention of reflecting the country's diversity. In
order to avoid the creation of a database that could be mined and
studied for difference by race, individual samples are not identified
racially, rather, continental origin for the entire panel is presented.
It remains to be seen whether this strategy will overcome the strong
tendency of researchers who wish to stratify their samples according to
"traditional" categories of race. It is, however, an example
of a rare public policy choice--a decision to avoid the imposition of
categories of difference that do not adequately reflect actual genetic
variation in the human population. |
