Mixed Race Studies

Education, Genetic Ancestry, and Blood Pressure in African Americans and Whites

American Journal of Public Health
August 2012, Volume 102, Number 8
pages 1559-1565
DOI: 10.2105/AJPH.2011.300448

Amy L. Non, Assistant Professor of Anthropology,
Vanderbilt University, Nashville, Tennessee

Clarence C. Gravlee, Associate Professor of Anthropology;  affiliate appointments in the Department of Behavioral Science and Community Health
University of Florida, Gainesville

Connie J. Mulligan, Professor of Anthropology; Associate Director, University of Florida Genetics Institute
University of Florida, Gainesville

• Objectives. We assessed the relative roles of education and genetic ancestry in predicting blood pressure (BP) within African Americans and explored the association between education and BP across racial groups.
• Methods. We used t tests and linear regressions to examine the associations of genetic ancestry, estimated from a genomewide set of autosomal markers, and education with BP variation among African Americans in the Family Blood Pressure Program. We also performed linear regressions in self-identified African Americans and Whites to explore the association of education with BP across racial groups.
• Results. Education, but not genetic ancestry, significantly predicted BP variation in the African American subsample (b = –0.51 mm Hg per year additional education; P = .001). Although education was inversely associated with BP in the total population, within-group analyses showed that education remained a significant predictor of BP only among the African Americans. We found a significant interaction (b = 3.20; P = .006) between education and self-identified race in predicting BP.
• Conclusions. Racial disparities in BP may be better explained by differences in education than by genetic ancestry. Future studies of ancestry and disease should include measures of the social environment. (Am J Public Health. 2012; 102:1559–1565. doi:10.2105/AJPH.2011.300448)

In recent decades, researchers have struggled to determine the causes of racial disparities in health. Many biomedical researchers have speculated that underlying genetic differences between races may contribute to these disparities. With the increasing availability of high-throughput genotyping platforms, a wealth of genomic data is now available to help address this issue. One consequence is that more researchers are estimating genetic ancestry to capture a presumed genetic basis of racial disparities in health. However, any associations found between genetic ancestry and disease could alternatively be explained by unmeasured environmental factors that are also associated with African genetic ancestry and contribute to health disparities, such as socioeconomic status (SES), neighborhood environment, and psychosocial factors including perceived stress or discrimination. Therefore, to avoid unwarranted inferences about the magnitude of genetic influences on health disparities, it is critical for any analysis of ancestry and disease to include appropriate social–environmental variables.

Social–environmental factors may be especially important when one is studying a complex disease such as hypertension. Complex diseases, by definition, involve multiple environmental and genetic causes, as well as interactions within and between them. Many studies have identified important social–environmental influences on racial inequalities in hypertension, such as SES, psychosocial stressors, and neighborhood environment, whereas other studies have begun to identify relevant genetic variants, such as those in the rennin–angiotensin–aldosterone axis and the adrenergic system. Few studies, however, have examined genetic and environmental factors simultaneously. The limited scope of this research to date has slowed progress toward explaining racial inequalities in hypertension and other complex diseases.

To address the relevance of both genetic and environmental factors in racial inequalities in hypertension, we tested associations between genetic ancestry, education, and blood pressure (BP) among Whites and African Americans in the Family Blood Pressure Program (FBPP) study. A previous analysis of this data set by Tang et al. found no evidence of a statistically significant association between African genetic ancestry and blood pressure. They concluded nonetheless that the results were “suggestive of genetic differences between Africans and non-Africans that influence blood pressure, but such effects are likely to be modest compared to environmental ones.” No environmental variables were included in their study, however. Here we reexamine the FBPP data set to test how the addition of education affects the association between ancestry and BP in African Americans. We also explored the association between education and blood pressure across racial groups. We hypothesized that education would show a greater association with BP than would African ancestry among African Americans, and that the association between education and BP may vary by racial and gender groups…

Read the entire article here.

The Correspondence Between Interracial Births and Multiple-Race Reporting

American Journal of Public Health
Volume 92, Number 12 (December 2002)
pages 1976–1981

Jennifer D. Parker, PhD
Office of Analysis, Epidemiology, and Health Promotion
National Center for Health Statistics, Hyattsville, Maryland

Jennifer H. Madans, PhD, OD Co-Deputy Director / OD Associate Director for Science / OPBL Associate Director
Office of Surveillance, Epidemiology, and Laboratory Services
Centers for Disease Control

• Objectives. Race-specific health statistics are routinely reported in scientific publications; most describe health disparities across groups. Census 2000 showed that 2.4% of the US population identifies with more than 1 race group. We examined the hypothesis that multiple-race reporting is associated with interracial births by comparing parental race reported on birth certificates with reported race in a national health survey.
• Methods. US natality data from 1968 through 1998 and National Health Interview Survey data from 1990 through 1998 were compared, by year of birth.
• Results. Overall multiple-race survey responses correspond to expectations from interracial births. However, there are discrepancies for specific multiple-race combinations.
• Conclusions. Projected estimates of the multiple-race population can be only partially informed by vital records. (Am J Public Health. 2002;92:1976–1981)

Eliminating racial disparities is an important national health objective; as a result, many policy and summary reports report race-specific health statistics to monitor trends and identify problem areas. Scientific research papers analyze race-specific data in hopes of understanding the disparities and, ultimately, finding ways to reduce them.

In 1997, the Office of Management and Budget (OMB) issued a revision to the long-standing directive for the collection of race and ethnicity data within the federal statistical system, known as OMB-15. Among other modifications designed to reflect the changing racial and ethnic profile in the United States, the 1997 standard requires that new data collections allow individuals to report 1 or more race groups when responding to a query on their racial identity. Analysts examining previously available data hypothesized that up to 2% of respondents to surveys or administrative collections would report 2 or more groups under the new standard. About 2.4% of the US population, nearly 7 million people, reported 2 or more race groups in the 2000 decennial census.

The impact of multiple-race reporting on statistics used for health policy and research is not yet known. It is likely that multiple-race respondents differ from each other and from their single-race counterparts on many measures of health and access to care. The extent of these differences will depend on many factors. All considered, multiple-race reporting will influence public health policy for both the newly tabulated multiple-race groups and the remaining single-race groups, which will be changed as a result of a wider choice of racial identification. Interracial births have increased over the past 3 decades. In the early 1970s, 1.4% of infants were born to parents who reported different race groups; by 1998, this percentage had increased to 4.3%. It would be reasonable to assume that individuals with parents of different races would identify with and report more than 1 group when responding to surveys and other data collections. However, how interracial births affect multiple-race reporting is unclear.

This report compares year- and race-specific national estimates of interracial births with year-specific survey estimates of multiple-race reporting. We compared the distribution of parental race for births from 1968 through 1998 with the reporting of more than 1 race for survey respondents in the 1990–1998 National Health Interview Survey (NHIS) who were born from 1968 through 1998. If all individuals with interracial parents reported both race groups on the survey, we would expect the distribution of multiple-race responses on the NHIS to coincide with the distribution of interracial births from birth records for the appropriate age–year combination. For example, the race distribution for births in 1970 would correspond to the race reported among the respondents who were aged 20 years in the 1990 NHIS, who were 21 in the 1991 NHIS, and so on. We would also expect that the inclusion of individuals with 1 or both parents who themselves identify with more than 1 race group may increase the percentages of multiple-race responses in the NHIS even more. Although neither the NHIS nor the birth certificate were developed to provide national race distributions, both data sources are routinely used to provide national estimates of races-specific health outcomes…

Read the entire article here.

The 1850 census marked a watershed in census-taking in several ways. For our purposes, a large part of its significance rests in the introduction of the “mulatto” category and the reasons for its introduction. This category was added not because of demographic shifts, but because of the lobbying efforts of race scientists and the willingness of certain senators to do their bidding. More generally, the mulatto category signaled the ascendance of scientific authority within racial discourse. By the 1850s, polygenist thought was winning a battle that it had lost in Europe. The “American school of ethnology” distinguished itself from prevailing European racial thought through its insistence that human races were distinct and unequal species. That polygenism endured at all was a victory, since the European theorists to abandon it. Moreover, there was considerable resistance to it in the United States. Although most American monogenists were not racial egalitarians, they were initially unwilling to accept claims of separate origins, permanent racial differences, and the infertility of racial mixture. Polygenists deliberately sought hard statistical data to prove that mulattoes, as hybrids of different racial species, were less fertile than their pure-race parents and lived shorter lives.

Melissa Nobles, “History Counts: A Comparative Analysis of Racial/Color Categorization in US and Brazilian Censuses,” American Journal of Public Health, Volume 90, Number 11 (November 2000): 1738-1745.

Virginia has made the first serious attempt to stay or postpone the evil day when this is no longer a white man’s country. Her recently enacted law “for the preservation of racial integrity” is, in the words of Major E. S. [Earnest Sevier] Cox, “the most perfect expression of the white ideal, and the most important eugenical effort that has been made during the past 4,000 years.”

W. A. Plecker, “Virginia’s Attempt to Adjust the Color Problem,” The American Journal of Public Health, Volume 15, Number 2 (1925): 111-115. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1320724/.

Paradigm Lost: Race, Ethnicity, and the Search for a New Population Taxonomy

American Journal of Public Health
Volume 91, Number 7 (July 2001)
pages 1049-1056
DOI: 10.2105/AJPH.91.7.1049

Gerald M. Oppenheimer, Professor of Clinical Sociomedical Sciences
Columbia University Mailman School of Public Health

The Institute of Medicine (IOM) recently recommended that the National Institutes of Health (NIH) reevaluate its employment of “race,” a concept lacking scientific or anthropological justification, in cancer surveillance and other population research. The IOM advised the NIH to use a different population classification, that of “ethnic group,” instead of “race.” A relatively new term, according to the IOM, “ethnic group” would turn research attention away from biological determinism and toward a focus on culture and behavior.

This article examines the historically central role of racial categorization and its relationship to racism in the United States and questions whether dropping “race” from population taxonomies is either possible or, at least in the short run, preferable. In addition, a historical examination of “ethnicity” and “ethnic group” finds that these concepts, as used in the United States, derive in part from race and immigration and are not neutral terms; instead, they carry their own burden of political, social, and ideological meaning.

Read the entire article here.

What is most disturbing about the paradoxical use of race is the effect it may have on the trajectory of ongoing human genetic variation research. By making the moral argument that race-based therapeutics address injustice in health care, and at the same time maintaining that genetics research will ultimately eliminate the need for racial categories, racialization is allowed to proceed unchallenged despite its inherent contradictory claims that race is both biologically meaningful and meaningless. Rather than serving as a way station, the use of race is allowed to become more fully embedded in the production of scientific knowledge and medical practice.

Sandra Soo-Jin Lee, “Racializing Drug Design: Implications of Pharmacogenomics for Health Disparities,” American Journal of Public Health, Volume 95, Number 12 (December 2005): 2137. http://dx.doi.org/10.2105/AJPH.2005.068676.

Racializing Drug Design: Implications of Pharmacogenomics for Health Disparities

American Journal of Public Health
Volume 95, Number 12 (December 2005)
pages 2133-2138
DOI: 10.2105/AJPH.2005.068676

Sandra Soo-Jin Lee, Senior Research Scholar
Stanford Center for Biomedical Ethics
Stanford University

Current practices of using “race” in pharmacogenomics research demands consideration of the ethical and social implications for understandings of group difference and for efforts to eliminate health disparities. This discussion focuses on an “infrastructure of racialization” created by current trajectories of research on genetic differences among racially identified groups, the use of race as a proxy for risk in clinical practice, and increasing interest in new market niches by the pharmaceutical industry.

The confluence of these factors has resulted in the conflation of genes, disease, and race. I argue that public investment in pharmacogenomics requires careful consideration of current inequities in health status and social and ethical concerns over reifying race and issues of distributive justice.

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History Counts: A Comparative Analysis of Racial/Color Categorization in US and Brazilian Censuses

American Journal of Public Health
Volume 90, Number 11 (November 2000)
pages 1738-1745

Melissa Nobles, Arthur and Ruth Sloan Professor of Political Science
Massachusetts Institute of Technology

Categories of race (ethnicity, color, or both) have appeared and continue to appear in the demographic censuses of numerous countries, including the United States and Brazil. Until recently, such categorization had largely escaped critical scrutiny, being viewed and treated as a technical procedure requiring little conceptual clarity or historical explanation. Recent political developments and methodological changes, in US censuses especially, have engendered a critical reexamination of both the comparative and the historical dimensions of categorization. The author presents a comparative analysis of the histories of racial/color categorization in American and Brazilian censuses and shows that racial (and color) categories have appeared in these censuses because of shifting ideas about race and the enduring power of these ideas as organizers of political, economic, and social life in both countries. These categories have not appeared simply as demographic markers. The author demonstrates that censuses are instruments at a state’s disposal and are not simply detached registers of population and performance.

…1850–1920 Censuses

The 1850 census marked a watershed in census-taking in several ways. For our purposes, a large part of its significance rests in the introduction of the “mulatto” category and the reasons for its introduction. This category was added not because of demographic shifts, but because of the lobbying efforts of race scientists and the willingness of certain senators to do their bidding. More generally, the mulatto category signaled the ascendance of scientific authority within racial discourse. By the 1850s, polygenist thought was winning a battle that it had lost in Europe. The “American school of ethnology” distinguished itself from prevailing European racial thought through its insistence that human races were distinct and unequal species. That polygenism endured at all was a victory, since the European theorists to abandon it. Moreover, there was considerable resistance to it in the United States. Although most American monogenists were not racial egalitarians, they were initially unwilling to accept claims of separate origins, permanent racial differences, and the infertility of racial mixture. Polygenists deliberately sought hard statistical data to prove that mulattoes, as hybrids of different racial species, were less fertile than their pure-race parents and lived shorter lives.

Racial theorist, medical doctor, scientist, and slaveholder Josiah Nott lobbied certain senators for the inclusion in the census of several inquiries designed to prove his theory of mulatto hybridity and separate origins. In the end, the senators voted to include only the category “mulatto,” although they hotly debated the inclusion of another inquiry—“[d]egree of removal from pure white and black races”—as well. Instructions to enumerators for the slave population read, “Under heading 5 entitled ‘Color,’ insert in all cases, when the slave is black, the letter B; when he or she is a mulatto, insert M. The color of all slaves should be noted.” For the free population, enumerators were instructed as follows: “in all cases where the person is black, insert the letter B; if mulatto, insert M. It is very desirable that these particulars be carefully regarded.”

The 1850 census introduced a pattern, especially in regard to the mulatto category, that lasted until 1930: the census was deliberately used to advance race science. Such science was fundamental to, though not the only basis of, racial discourse—that is, the discourse that explained what race was. Far from merely counting race, the census was helping to create race by assisting scientists in their endeavors. Although scientific ideas about race changed over those 80 years, the role of the census in advancing such thought did not.

The abolition of slavery and the reconstitution of White racial domination in the South were accompanied by an enduring interest in race. Predictably, the ideas that race scientists and proslaveryadvocates had marshaled to defend slavery were used to oppose the recognition of Black political rights. Blacks were naturally inferior to Whites, whether as slaves or as free people, and should therefore be disqualified from full participation in American economic, political, and social life. Although scientists, along with nearly all Whites, were convinced of the inequality of races, they continued in their basic task of investigating racial origins. Darwinism presented a challenge to the still dominant polygenism, but the mulatto category retained its significance within polygenist theories. Data were needed to prove that mulattoes lived shorter lives, thus proving that Blacks and Whites were different racial species…

…The mulatto category remained on the 1910 and 1920 censuses for the same reason that it had been introduced in 1850: to build racial theories. (Census officials removed the category from the 1900 census because they were dissatisfied with the quality of 1890 mulatto, octoroon, and quadroon data.) The basic idea that distinct races existed and were enduringly unequal remained firmly in place. What happens when superior and inferior races mate? Social and natural scientists still wanted to know. But the advisory committee to the Census Bureau decided in 1928 to terminate use of the mulatto category on censuses.

The stated reasons for removal rested on accuracy. Had the advisory committee possessed confidence in the data’s accuracy or the Census Bureau’s ability to secure accuracy, “mulatto” might well have remained on the census. The committee did not refer to the evident inability of the mulatto category to settle the central, if shifting, questions of race science: first,whether “mulatto-ness” proved that Whites and Blacks were different species of humans, and then, whether mulattoes were weaker than members of the so-called pure races. The exit of the mulatto category from the census was markedly understated, especially whencompared with its entrance in 1850 and its enduring significance on 19th-century censuses.

Beginning with the 1890 census, all Native Americans,whether taxed or not,were counted on general population schedules. Much as racial theorists believed that enumerating mulattoes would prove their frailty, they thought that Native Americans were a defeated and vanishing race. Given the weight of these expectations in the late 19th century, it is not surprising that census methods and data reflected them. As the historian Brian Dippieobserved, “the expansion and shrinkage of Indian population estimates correlate with changing attitudes about the Native American’s rights and prospects.” The idea of the vanishing Indian was so pervasive that the censuses of 1910 and 1930 applied a broad definition of “Indian” because officials believed that each of these censuses would be the last chance for an accurate count.

Read the entire article here.

Why genes don’t count (for racial differences in health)

American Journal of Public Health
Volume 90, Number 11 (November 2000)
pages 1699-1702
DOI: 10.2105/AJPH.90.11.1699

Alan H. Goodman, Professor of Biological Anthropology
Hampshire College, Amherst, Massachusetts

There is a paradoxical relationship between “race” and genetics. Whereas genetic data were first used to prove the validity of race, since the early 1970s they have been used to illustrate the invalidity of biological races. Indeed, race does not account for human genetic variation, which is continuous, complexly structured, constantly changing, and predominantly within “races.” Despite the disproof of race-as-biology, genetic variation continues to be used to explain racial differences. Such explanations require the acceptance of 2 disproved assumptions: that genetic variation explains variation in disease and that genetic variation explains racial variation in disease. While the former is a form of geneticization, the notion that genes are the primary determinants of biology and behavior, the latter represents a form of racialization, an exaggeration of the salience of race. Using race as a proxy for genetic differences limits understandings of the complex interactions among political-economic processes, lived experiences, and human biologies. By moving beyond studies of racialized genetics, we can clarify the processes by which varied and interwoven forms of racialization and racism affect individuals “under the skin.”

…Professor Armelagos hinted at a powerful lesson: that scientific ideas can endure and be made to seem real if they have social and political–economic utility. An evolutionary framework that explained human variation had been established for more than a century, ever since the publication of Darwin’s Origin of Species. In the 1940s, Montagu used the “new evolutionary synthesis” to explain clearly why race was a biological myth. Yet the idea of race as biology persists today in science and society.

I was aware of the power of race as a worldview in 1973. But what I understood less was the idea’s ability to persist after it had been proven unscientific. If I had been asked in the 1970s whether race would survive as a way to think about human biological variation in 2000, I would have answered emphatically, “No!” I was naive to the durability of an economically useful idea.

Acceptance of the notion of race-as-biology declined in anthropology throughout the late 1970s and early 1980s. Yet, during the past decade, racialized notions of biology have made a comeback. This is especially true in human genetics, a field that, paradoxically, once drove the last nail into the coffin of race-as biology. In this commentary, I explain why race should not be used as a proxy for genetic or biological variation. I then explain and illustrate the unfounded assumptions that are needed for an acceptance that racial differences in disease are due to genetic differences among races…

…The Double Error Inherent in Genetic Explanations of Racial Differences

Two errors—2 leaps of illogic—are necessary for acceptance of the idea that racial differences in disease are due to genetic differences among races. The first leap is a form of geneticization, the belief that most biology and behavior are located “in the genes.”

Genes, of course, are often a part of the complex web of disease causality, but they are almost always a minor, unstable, and insufficient cause. The presence of Gm allotype, for example, might correlate to increased rates of diabetes in Native Americans, but the causal link is unknown. In other cases, the gene is not expressed without some environmental context, and it may interact with environments and other genes in nonadditive and unpredictable ways.

The second necessary leap of illogic is a form of scientific racialism, the belief that races are real and useful constructs. Importantly, this leap propels one from explaining disease variation as caused by genetic variation to explaining that racial differences in disease are caused by genetic variation among races.To accept this logic, one needs to also accept that genetic variation occurs along racial divides: that is, most variation occurs among races. However, we know from Lewontin’s work that this assumption is false for simple genetic systems. For a disease of complex etiology, genetics is an illogical explanation for racial differences.

Read the entire article here.

Criollo, Mestizo, Mulato, LatiNegro, Indígena, White, or Black? The US Hispanic/Latino Population and Multiple Responses in the 2000 Census

American Journal of Public Health
Volume 90, Number 11 (November 2000)
pages 1724-1727

Hortensia Amaro, Distinguished Professor of Health Sciences and of Counseling Psychology
Bouve College of Health Sciences
Northeastern University

Ruth E. Zambrana, Profesor of Womens Studies
University of Maryland

Current dialogues on changes in collecting race and ethnicity data have not considered the complexity of tabulating multiple race responses among Hispanics. Racial and ethnic identification—and its public reporting–among Hispanics/Latinos in the United States is embedded in dynamic social factors. Ignoring these factors leads to significant problems in interpreting data and understanding the relationship of race, ethnicity, and health among Hispanics/Latinos. In the flurry of activity to resolve challenges posed by multiple race responses, we must remember the larger issue that looms in the foreground—the lack of adequate estimates of mortality and health conditions affecting Hispanics/Latinos. The implications are deemed important because Hispanics/Latinos will become the largest minority group in the United States within the next decade.

Read the entire article here.