Book Review: Medical Apartheid by Harriet A. Washington

On the Father’s day Sunday this year, I was at the Salem Baptist Church, south side mega church, for prostate specific antigen (PSA) screening and PSA study recruitment event.  We offered PSA screening for prostate cancer several occasions at this church and this church has an annual health event to encourage African American church members to have healthier lifestyle.  Five out of eight people who were working in the screening event that day were African Americans, including the PI of the project, who is African American male urologist at Northwestern medical school.  The first African American man who came in for PSA screening jokingly said, “Ok, I will be the first guinea pig.  What do I have to do?”

African American men have poorer health conditions compared to African American women or European American men and women, but African American men are usually underrepresented in many medical research projects, most likely due to difficulty recruiting them for medical research projects or clinical trials.  Why is it so difficult to recruit African American men?  Why do they refuse to participate in medical research?

This book, “Medical Apartheid,” illustrates the reasons why it is difficult to recruit African Americans for medical research and why they mistrust physicians or medical institutions rooted in the American history beginning the enslavement of Africans.  The author, Harriet A. Washington, illustrates history of injustice in health, not from the victors’ perspective.  The advance in medical science was achieved some way through exploitation of African Americans, but was hindered at the same time because of flaws in their research designs, scientific methods, and reasoning.

Considering the history of slavery and racial segregation, it was not surprising to read that White doctors did not treat the slaves like they would for white patients.  Slave owners, physicians’ real clients, did not want to spend much money to treat their slave, if treatment cost more than they could make a profit from their slaves.  African Americans knew that white doctors’ treatments did not work well or worsened the problems, and preferred their traditional healing methods (p.48).  Even after the slavery ended, African Americans suffered with poor health conditions because they did not have access to good health care due to low income, no health insurance, and poor living environments (p. 152).  Medical racism continued until recently, and medical procedures, such as hysterectomy, were done to African Americans and they were recruited to medical research without them fully understanding medical procedures, experiments, or research.

It was very surprising to read that a various painful and dangerous medical experiments were done to African Americans either poorly informed or without consent, without anesthesia during the slavery.  Tuskegee Syphilis Study that followed untreated African American men with syphilis over 40 years and performed autopsy for hundred subjects is well known, but there are many more.  For example, James Marion Sims, father of American gynecology, developed a surgical treatment for vesicovaginal fistula using slave women as experimental subjects (p.61-68).

Even after 1950s, medical experimentation targeted vulnerable segments of American society, low-income African Americans, prisoners, and children.  Between 1944 and 1994, nontherapeutic radiation was injected to study subjects, and African American had higher risk of being the subject of the experiments.  African Americans were targeted to experiment of biological weapon as well (p. 361-363).  Washington states that many African American subjects who went through medical experiments and African American patients who received medical procedures involuntary thought that physicians were really caring them (p. 219).  Washington further states that medical abuse is far from over and medical experimentations are still performed on people of African descent in this country as well as in Africa (p. 386-396).

Scientific racism was a major paradigm in the 19th century in the U.S. and Europe to show that African Americans and African as inferior subspecies of human.  Scientists and physicians tried to show scientifically that there are anatomical and physiological differences, such brain size, immune system, and skin color, and the body of African Americans were displayed in St. Louis World’s Fair in 1906, a zoo in New York City, and a saloon in New York City transformed into an operation room, to prove that African Americans and Africans were inferior.

Washington sees the contradictions.  Even though White physicians believed that African Americans were physically different from European Americans, African Americans were treated as a ‘clinical material’ in medical schools for instruction and experiment (p.106-108).  Unnecessary surgeries were performed to demonstrate clinical procedure to the medical students.  After death, their bodies were used for dissection, even in Georgia where anatomical dissection was illegal until 1887 and in northern states, using stolen bodies from graves (p.120).  Northern states imported African American bodies for dissection from southern states (p.123).

Today, clinical trial is one way to receive the best treatment available, especial for the people with an advanced disease condition and traditional established treatment methods failed to cure or improve their health.  However, African Africans are more likely to be recruited for high risk clinical trials for a newly developed HIV drag or an implantation of artificial heart than European Americans, but poor minority populations are less likely to be able to receive the expensive treatments after they are developed.  African Americans who have been subjected to experiments as a ‘clinical material’ may see clinical trial differently.  Washington quotes the Richmond Daily Dispatch published in 1854 saying that African Americans believed if they entered medical school hospital, they would not come out alive (p.108).

Having read this book, it is understandable if African Americans do not want to participate in clinical trial or medical research.  African American patients are feeling anxious about their medical conditions, when they come to a clinic in a hospital, an institutions that have similar social structure as in slavery.  Many physicians, high-rank nurses and administrative stuffs are European Americans, while lower-rank hospital stuffs are minorities.  Some hospital and medical school buildings have architectural styles and motives that symbolize the power of European civilization.

Embodiment of social inequality causes health disparities

Krieger, N. 2012 Methods for scientific study of discrimination and health: An ecosocial approach. American Journal of Public Health 102(5):936-945.

In this paper, Krieger explains how discrimination based on racial/ethnic origins affects health of the racial/ethnic minorities.  She uses a bio-cultural approach to understand the interactions between social aspects (social structure, economic and social derivation, individual’s life-long experience of racism, and individuals’ cognitive aspects) and biological aspects of race (physical traits and exposures to toxins, hazards, and pathogens).  This approach incorporates the temporal (life-cycles starting in utero to the end of life) and spatial (from individual to global level) aspects that affect minority health.  While incorporating the wide variety of aspects of minority individuals and societies into her theoretical framework, she focuses on the causal relationship between discrimination and health, so she sees health inequality is manifestation of social inequality.

But we really need to look at these tables from her paper to understand the social context.

Table 1 Analyzing US Racial/Ethnic Health Inequities in Context

There are more African Americans living at poverty level, unemployed, and without health insurance compared to European Americans.  Infant mortality rate is much higher among African Americans, and more African American self-report having poor health status.  Minority groups are underrepresented in the congress and state legislature.

Table 3 Postelection National Poll Results for Statement on Racial Discrimination, November 3-7, 2010

However, so many white Americans and Tea Party and Republicans agree that “Today discrimination against Whites has become as big a problem as discrimination against Blacks and other minorities.”

The core concept in her approach is embodiment of social inequality.  I believe the concept of embodiment came from habitus, idea developed by Pierre Bourdieu, a French social theorist who also talked about social capital.  Embodiment is one of the core aspects of habitus, and I believe it means that people’s e experience, material word, and social structure are incorporated deep into one’s cognition.  Krieger develops this concept further to reflect biological aspects related to health inequality.  Because of discrimination, racial minorities are more likely to be exposed toxins, hazards, and pathogens and surfer from economic and social deprivation and inadequate medical care, so racial minorities are more likely to have worse health condition.

I believe embodiment is the concept that we should explore in our research and could be very useful to analyze social determinants of health.  For example, we can use this idea to analyze the relationship between fast food culture and health.  In the U.S. fast food restaurants are fun place for kids and provide quick and inexpensive food for teenagers and adults.  It is culturally acceptable to go to fast food restaurant regularly, if you do not have time and money.  The food tastes good for kids and fills adults’ stomach for a long time.  Over time, we develop the taste for fast food, and going to fast food restaurant became an integrated part of people’s life and cognition.  People who grow up with fast food restaurants now have children and take them there regularly.  It is not surprising if these children prefer French fries over vegetables.  Because of targeted marketing and economic condition, low-income individuals, and many of them are racial/ethnic minorities, are more likely to be exposed to these high fat high calories diet.

While she focuses on racial discrimination as one of the causes of health inequality, her ecosocial approach seems to be a holistic framework for analysis of social determinants of health.  Human and our societies are very complex, we need a framework as holistic as possible to capture multidimensional aspects of human societies (social determinants of health, racism, etc.) and human biology (health).

Because her focus in this paper was explaining the causal relationship between discrimination and health, she did not explain how this framework can be used to reduce health inequality.  If we can identify the social issue related to racism and health that we hope to fix, how can we use this approach to develop a strategies for intervention?

Why I am interested in genetic epidemiological study of prostate cancer: Is prostate cancer disparities due to gene or environment?

Prostate cancer is the most common cancer among men in the U.S., and African American men have 63% higher incidence compared to European American men.  Prostate cancer incident rate was 228.8 cases per 100,000 in African American men from 2005 to 2009, while the incidence rate was 140.3 per 100,000 in European American men (DeSantis et al. 2013).  Globally, African descent men have high incidence and mortality (Rebbeck et al. 2013), and incidence of prostate cancer is rising in African countries.  Only established risk factors for prostate cancer are age, family history, and race/ethnicity, and the cause for disparities in prostate cancer incidence is still not well understood.

Environmental and social/cultural factors may play roles for increasing prostate cancer risk among African descent men, but the causal relationship of any environmental and social/cultural factors with prostate cancer risk is not well demonstrated.  Many suggest that diet likely plays roles for Pca risk.  For example, differences in serum vitamin D levels between African Americans and European Americans have been well demonstrated, and some suggested that differences in vitamin D levels may explain prostate cancer disparities.  However, epidemiological studies, mainly conducted in people of European descent, show inconsistent results.

Access to health care, socioeconomic status, neighborhood derivation, and other socio-cultural factors affect stage and tumor grade at the diagnosis, treatment choice, and mortality, but these factors may not explain the difference in prostate cancer incidence.

On the other hand, there is strong evidence for genetic factors that explain increased incidence in African Americans.  Admixture mapping identified loci at 8q24 region showing association between African genetic ancestry and prostate cancer risk (Freedman et al. 2006).  Admixture mapping takes advantage of long-range linkage disequilibrium (LD) in recently admixed populations such as African Americans and Hispanic Americans, and with use of ancestry informative markers (AIMs) that have large allele frequency differences between ancestral populations, fewer number of markers is required to capture genomic variation than genome wide association study (GWAS).  This approach is powerful, when the prevalence of disease is different between two populations and used to identify genomic region that are associated with many diseases that have different prevalence between populations (Batai and Kittles 2013).  Association of 8q24 variants with prostate cancer has been replicated in African Americans, Caribbeans, and West Africans.  In addition, GWAS among African American identified a novel locus at 17q21 associated with Pca (Haiman et al. 2011).

GWAS among European and Asian populations identified number of prostate cancer susceptibility loci, but the replication of GWAS identified loci in AA has been difficult (Batai et al. 2012), and we have a lot of work ahead of us to understand how genetic factors affect prostate cancer risk in African American men


Batai K, and Kittles RA. 2013. Race, Genetic Ancestry, and Health. Race Social Problems 5:81-87.

Batai K, Shah E, Murphy AB, Newsome J, Ruden M, Ahaghotu C, and Kittles RA. 2012. Fine-Mapping of IL16 Gene and Prostate Cancer Risk in African Americans. Cancer Epidemiology Biomarkers & Prevention 21(11):2059-2068.

DeSantis C, Naishadham D, and Jemal A. 2013. Cancer statistics for African Americans, 2013. CA: A Cancer Journal for Clinicians 63(3):151-166.

Freedman ML, Haiman CA, Patterson N, McDonald GJ, Tandon A, Waliszewska A, Penney K, Steen RG, Ardlie K, John EM et al. . 2006. Admixture mapping identifies 8q24 as a prostate cancer risk locus in African-American men. Proceedings of the National Academy of Sciences 103(38):14068-14073.

Haiman CA, Chen GK, Blot WJ, Strom SS, Berndt SI, Kittles RA, Rybicki BA, Isaacs WB, Ingles SA, Stanford JL et al. . 2011. Genome-wide association study of prostate cancer in men of African ancestry identifies a susceptibility locus at 17q21. Nature Genetics 43(6):570-573.

Rebbeck TR, Devesa SS, Chang B-L, Bunker CH, Cheng I, Cooney K, Eeles R, Fernandez P, Giri VN, Gueye SM et al. . 2013. Global Patterns of Prostate Cancer Incidence, Aggressiveness, and Mortality in Men of African Descent. Prostate Cancer 2013:12.

Race, Genetic Ancestry, and Health: A Direction for Anthropological Genetics in the 2010’s?

Batai, K. and R. A. Kittles (2013). “Race, Genetic Ancestry, and Health.” Race and Social Problems 5(2): 81-87.

In June 2013 edition of Race and Social Problems journal, we published this review article.  I think, for anthropologists who have a training in genetics, it is an interesting direction that we should explore more.  When I was almost done with my dissertation work, I began to think what I could do after I got my degree.  I was dissatisfied with anthropological genetics.  Although I was excited to investigate human genetic variation and evolution and had fun learning and teaching (I am still interesting in these topic and continue to explore), I felt “so what?”  I understand the importance of understanding migration history and genetic variation in the world, but I felt that anthropologists and many people, mostly wealthy people, are interested in human past and variation mostly only for their intellectual interests.  Who really care about our findings?  Are they really useful knowledge?

Then, I began thinking about using anthropological perspectives and methods to help other people.  I contacted my current mentor, Dr. Rick Kittles, to see if I could do genetic research on health disparities.  I learnt genetic epidemiology, a study of roles of genetics in determining or influencing disease risk in families or populations.  In the genetic epidemiology, a lot of population genetics knowledge and methods are applied to the basic epidemiological research design.  More recently, genetic epidemiologists are showing interests in gene and environment interactions.  Here, environment refers to lifestyle and socio-cultural factors.  Gene and environmental interactions is basically what anthropologists call “bio-cultural perspective,” but genetic epidemiologists think more statistically.

In the U.S., we see a great racial health disparities.  Differences in access to health care and health screen can explain a part of health disparities, but there are more complex, genetic, biological, and socio-cultural factors that are intertwined with ‘race.’  Anthropologists are trained to understand this complex relationship.  We can bring different insights in the genetic research of health disparities from scientists who were trained in other fields, and we can contribute to biomedical science in unique ways.

Social and cultural factors are better predictors of blood pressure in African Americans more than genetic ancestry

The association between genetic ancestry and skin color has been well demonstrated (see here).  The heritability of skin color is quite high suggesting that contribution of genetic components to skin color is high as well.  Many genetic research projects support this showing that variants in pigmentation candidate genes are associated with skin color or other pigmentation traits (reviewed here).  However, it is often difficult to demonstrate the association between genetic ancestry and common diseases because social-cultural factors (socio-economic status, education, income, employment status, access to health care, etc.) confound the relationship.

The association between skin color and blood pressure among African Americans has been investigated by many researchers (see here), but more recently researchers started using genetic ancestry estimates to test the association between African ancestry and blood pressure.  In genetic studies, information on only clinically relevant variables are collected, so association between genetic ancestry and disease phenotype (here blood pressure) is often tested without adjusting for socio-cultural and environmental factors.  Only a few studies conducted so far examined 1) effects of genetic ancestry and socio-cultural factors simultaneously and 2) interactions of these factors.

Non et al. (2012) explored the association between genetic ancestry and blood pressure and between education and blood pressure using publically available Family Blood Pressure Program (FBPP) study data.  They found that education, not genetic ancestry, was significantly associated with blood pressure in African Americans and interaction between education and race also plays a role in the racial difference in blood pressure.

First, they examined if African ancestry estimated using 294 autosomal STR was a predictor of blood pressure in African Americans.  They did not observe significant difference in African ancestry between hypertensive and non-hypertensive African Americans.  In the linear regression model, education was significantly associated with blood pressure but African ancestry was not.  They did not observe interaction between African ancestry and education either.

Second, they examined if education explains difference in blood pressure between African Americans and European Americans.  African Americans with high-school degree or who did not complete high-school degree have significantly higher blood pressure than people with higher educations.  They did not observe the same pattern in European American, however.  In the regression analysis, they observed the interaction between education and race.  In addition, they showed that decline in SBP is sharper with increasing educational levels in African Americans than in European Americans.

This is an interesting study to show that education (and probably poverty), not genetic ancestry, is a very important factor affecting blood pressure in African American, suggesting that obtaining higher education will benefit African Americans more than European Americans.  As noted by the authors, one of the limitations of this study is that education was only social-environmental factor available in the dataset and they used it as a proxy for socio-economic status and other social environmental factors.  While I agree that education can be very useful for capturing the many social-environmental factors and their analyses clearly show that socio-environmental factors measured with education are very important predictors or risk factors of blood pressure in African Americans, African American societies are too diverse and heterogeneous, and there should be many socio-environmental factors that affect blood pressure but not captured with education.  They also could explore more what socio-economic factors were captured with education.

It is interesting to note that anthropologically trained scientists are showing that socio-cultural factors are as important as genetic factors assessed with genetic ancestry estimates and skin color.  In other papers, Gravlee at al. (2005 and 2009) have shown that skin color or genetic ancestry is associated with blood pressure in Puerto Ricans, but social classification based on skin color is associated with blood pressure in Puerto Ricans.  They also observed statistically significant interaction between skin color and socio-economic status.


Gravlee, C. C., W. W. Dressler, et al. (2005). “Skin Color, social classification, and blood pressure in Southeastern Puerto Rico.” Am J Public Health 95(12): 2191-2197.

Gravlee, C. C., A. L. Non, et al. (2009). “Genetic ancestry, social classification, and racial inequalities in blood pressure in Southeastern Puerto Rico.” PLoS ONE 4(9): e6821.

Non, A. L., C. C. Gravlee, et al. (2012). “Education, genetic ancestry, and blood pressure in African Americans and Whites.” Am J Public Health 102(8): 1559-1565.


Is skin color associated with blood pressure in African Americans?

Anthropologists have been interested in evolution of skin color for a long time, but I believe that anthropologists and other scientists should study about it for many reasons.  Here is one of many reasons.

Boyle (1970) and others observed association between skin color and high blood pressure among African Americans long time ago, and in these studies, skin color was used as a proxy for admixture and Africa ancestry.  However, subsequent studies demonstrated complex relationship between skin color, socioeconomic status, and blood pressure.

For example, Klag et al. (1991) observed the association between skin color and blood pressure in African Americans, and they showed that darker-skinned African Americans tend to have increased blood pressure.  They also show that this association depends on the socioeconomic status.  Among African Americans in the lowest socioeconomic status, darker-skinned African Americans had considerably higher blood pressure level than lighter-skinned African Americans, but they did not observe the same pattern among the African Americans in the higher socioeconomic status.  In their multivariate regression analysis, they observed significant interaction between skin color and socioeconomic status associated only with diastolic blood pressure.  Moreover, they showed that whether African Americans completed high school education or not had a significant effect on blood pressure and again they observed statistically significant interaction between skin color and education (please note that survey data was collected between 1972-1974).

More recent study by Sweet et al. (2007) reported similar findings.  They also found that darker-skinned African Americans have higher blood pressure in the CARDIA study, and they found the significant interaction between skin color and income.  In a similar study of blood pressure, Gravlee at al. (2005) have shown that skin color is not associated with blood pressure in Puerto Ricans, but social classification based on skin color is associated with blood pressure in Puerto Ricans.

These studies show that both genetic/biological factors and socio-environmental factors have a great impact on blood pressure in African Americans.  The effects of both of these factors on blood pressure, and maybe on other disease phenotypes, should be examined simultaneously.


Boyle, E., Jr. (1970). “Biological patterns in hypertension by race, sex, body weight, and skin color.” JAMA: The Journal of the American Medical Association 213(10): 1637-1643.

Gravlee, C. C., W. W. Dressler, et al. (2005). “Skin Color, social classification, and blood pressure in Southeastern Puerto Rico.” Am J Public Health 95(12): 2191-2197.

Klag, M. J., P. K. Whelton, et al. (1991). “The association of skin color with blood pressure in us blacks with low socioeconomic status.” JAMA 265(5): 599-602.

Sweet, E., T. W. McDade, et al. (2007). “Relationships between skin color, income, and blood pressure among African Americans in the CARDIA study.” Am J Public Health 97(12): 2253-2259.

Genes associated with human pigmentation traits in Genome-Wide Association Studies (GWAS)

Although there are many issues, Genome-Wide association study (GWAS) has been a powerful method to identify genetic variants associated with phenotypic traits.  GWAS is generally used to find genetic variants associated with disease, but it also found variants associated with anthropometric traits, such as height and BMI.  Also, there are several GWAS mainly among people of European descents aiming to find genetic variants associated with pigmentation characteristics (hair, eye, and skin color, freckles, and skin sensitivity to sun or tanning ability) (e.g., Eriksson, 2010; Han, 2008; Kayser, 2008; Liu, 2010; Nan, 2009; Sulem, 2008; Sulem, 2007)   These GWAS identified variants associated with pigmentation characteristics on SLC45A2 (Chr5), IRF4 (Chr6), TYRP1 (Chr9), TYR (Chr11), KITLG (Chr12), SLC24A4 (Chr14), OCA2/HERC2 (Chr15), MC1R (Chr16), and ASIP (Chr20).  These studies showed very strong association of variants in these genes with hair color, eye color, freckles, sensitivity to the sun, and tanning ability.

However, because the skin color does not vary much in European populations, these GWAS were not very successful showing the association between genetic variants and skin pigmentation, and only one of these studies, in which people of non-European descents were included, successfully showed the association between skin color and an IRF4 variant (Han et al. 2008).

Another GWAS among South Asians demonstrated the association of skin color with variants in two genes (SLC45A2 and TYR), but the study also found that another gene, SLC24A5 (Chr15) is associated with skin color (Stokowski et al. 2007).  The association of SLC24A5 variants with skin color in African Americans has been reported previously (Lamason et al. 2005).  More recently, Kenny et al. report that an amino acid change in TYRP1 associated with blond hair among Solomon Islanders (Kenny, 2012).

Identifying these genetic variants is important not only to understand major human phenotypic variation and the mechanism of evolution of pigmentation traits, but also to find variants that may be associated with skin cancer and to understand the risk factors for vitamin D deficiency.  Because of admixture, African Americans exhibit a great range of skin color, so they are desirable for genetic study of skin pigmentation.

Eriksson, N., J. M. Macpherson, et al. (2010). “Web-Based, Participant-Driven Studies Yield Novel Genetic Associations for Common Traits.” PLoS Genet 6(6): e1000993.

Han, J., P. Kraft, et al. (2008). “A Genome-Wide Association Study Identifies Novel Alleles Associated with Hair Color and Skin Pigmentation.” PLoS Genet 4(5): e1000074.

Kayser, M., F. Liu, et al. (2008). “Three Genome-wide Association Studies and a Linkage Analysis Identify HERC2 as a Human Iris Color Gene.” American Journal of Human Genetics 82(2): 411-423

Kenny, E. E., N. J. Timpson, et al. (2012). “Melanesian Blond Hair Is Caused by an Amino Acid Change in TYRP1.” Science (New York, N.Y.) 336(6081): 554.

Lamason, R. L., M. A. Mohideen, et al. (2005). “SLC24A5, a putative cation exchanger, affects pigmentation in zebrafish and humans.” Science (New York, N.Y.) 310(5755): 1782-1786.

Liu, F., A. Wollstein, et al. (2010). “Digital Quantification of Human Eye Color Highlights Genetic Association of Three New Loci.” PLoS Genet 6(5): e1000934.

Nan, H., P. Kraft, et al. (2009). “Genome-Wide Association Study of Tanning Phenotype in a Population of European Ancestry.” J Invest Dermatol 129(9): 2250-2257.

Stokowski, R. P., P. V. K. Pant, et al. (2007). “A Genomewide Association Study of Skin Pigmentation in a South Asian Population.” American Journal of Human Genetics 81(6): 1119-1132.

Sulem, P., D. F. Gudbjartsson, et al. (2008). “Two newly identified genetic determinants of pigmentation in Europeans.” Nat Genet 40(7): 835-837.

Sulem, P., D. F. Gudbjartsson, et al. (2007). “Genetic determinants of hair, eye and skin pigmentation in Europeans.” Nat Genet 39(12): 1443-1452.