The Epigenetics of Being Black and Feeling Blue: Understanding African-American Vulnerability to Disease

by Darron T. Smith, Ph.D.

Black Americans have endured many hardships ever since twenty Africans set foot in Jamestown, Virginia in 1619. For 85% percent of our nation's existence, white-imposed systems of oppression via slavery and Jim Crow "separate but equal" were the bloody and violent norm.

Since that time, the persistence of racial discrimination has remained a routine part of their everyday experience. Black folk have worked very hard on a steady path of social mobility through group uplift and self-determination against overwhelming odds. 

In this milieu of racist deprivation, some black Americans have managed to find economic, political and other forms of success against the hegemonic countervailing forces of white institutional racism and all of its permutations that thwart black life as we know it. 

This systemic inequality has an impact on more than class position. It influences human biology and physiology at the cellular level, leaving the bodies of the poor, the impoverished, and the targeted more vulnerable to chronic disease.

Epigenetics is the science of how the external environment affects us at the molecular level by altering gene expression and function that can, in turn, be heritable. It refers to chemical modifications or "tags" that mark specific genes around the intricate DNA complex. 

These modifications can alter gene expression influencing our biology and function. Think of a tag as a volume control knob that signals the gene to turn up or down its programmed function. 

Our genes listen for cues from the environment such as the food we eat, the kind of milieus where we live and work, the circumstances of our birth, and the race and class-based interactions we share with one another. These factors, in part, determine how our genes respond in ways that expose more vulnerable populations to disease. 

Human wars, famines, droughts, plagues, physical and emotional abuse, and other forms of social deprivation not only leave their mark on society in harmful ways, but they also reek havoc deep within the cells of our bodies. The cells react to stressors in the larger social structure at crucial developmental times in the womb that have an influence on human health later in adult life, leaving us more sensitive to our environment and susceptible to disease. 

The longitudinal Dutch Famine Birth Cohort that began shortly after World War II in 1945 captures the complexity of environmental factors on our genes. The study analyzed the long-term physical and emotional effects in children who were exposed to maternal malnutrition in the fetal environment. 

They found that poor nutrition leads to epigenetic changes in gene regulation of the fetus and its developing biological systems, which predisposes cells to certain diseases of slow accumulation that include obesity, kidney disease, lung problems, cardiac disease, breast cancer, and a host of additional physical and mental health disorders. 

In epidemiology and other closely related social science disciplines, it has been well established that social-class position is inversely linked to poor health. Further, it is well known that health status follows a social gradient with class-based differences in disease frequencies that mirror society.African Americans are constantly relegated to the margins of society where there are continuously exposed to the mundane effects of white-imposed discrimination. 

Within this space, many African Americans endure daily hassles and sustained assaults for just being black. These micro-aggressions can have negative health-related consequences for their mental, emotional and physical wellbeing by epigenetically-altering the expression of certain cells that control for important bodily functions.

Research over the last four decades has mounted strong evidence that race-based mistreatment on the basis of physical characteristics (i.e., hair, bone, lips, skin color, eye shape, etc.) takes a heavy toll on black people not only at the social, political and economic levels of society, but also at the physiological level where cortisol, the body's "fight or flight" hormone, is seen at elevated levels in African Americans. DNA and its sequencing is genetically programmed to perform functions of the body such as this very stress response.

However, biological processes that regulate these functions can be epigenetically altered to increase the physiological stress response in the body at a rate higher and longer than what is normal. This, in turn, can influence the normal function of a cluster of differing cells that regulate blood pressure, kidney function, and cardiac function. Scientists can now investigate these epigenetic modifications on cells induced by the environment such as in the Dutch famine example.

The science of epigenetics is unlocking significant clues as to how racial discrimination can induce changes to the expression of certain genes linked to biological development and the existence of disease. These epigenetic changes can linger for a lifetime and can potentially be transmitted to offspring.

Because black Americans and their forbears have endured over 20 generations of white-imposed race-related inequities in every major sector in society, including persistent race-based discrimination in housing, education, healthcare, jobs, and the prison industrial complex, they carry a higher burden of disease.

Health and disease are no longer purely infectious in nature, but instead, social and environmental factors account for most chronic disease. It is a function of the dynamic interaction between our genes and the larger society, and epigenetics is providing deeper understanding as to how our genes operate in these situations. 

African Americans and their descendants have paid an exorbitantly high price for living in an unequal society in a number of reprehensible ways through the practice of forced labor, high incarceration rates, frequent under/unemployment and low educational expectation. And now, significant health care challenges are among the more salient forms of white on black discrimination. 

In the absence of sweeping governmental reforms that place human rights over property rights, African Americans must take greater ownership in their own health care by becoming better informed on effective ways to reduce stress--to the extent possible given the maintenance of systems of domination and oppression--to have an impact upon the quality of black life. 

Otherwise, these persistently elevated stress levels from chronic exposure to race-based discrimination have been shown to be physiologically and mentally bad for health and well-being, both at the individual and institutional levels of society. The result is epigenetic tags with harmful gene expressions.

Racism May Accelerate Aging in African-American Men

Date: January 7, 2014

Source: University of Maryland

A new study reveals that racism may impact aging at the cellular level. Researchers found signs of accelerated aging in African American men, ages reporting high levels of racial discrimination and who had internalized anti-Black attitudes. Findings from the study, which is the first to link racism-related factors and biological aging, are published in the American Journal of Preventive Medicine.

Racial disparities in health are well-documented, with African Americans having shorter life expectancy, and a greater likelihood of suffering from aging-related illnesses at younger ages compared to Whites. Accelerated aging at the biological level may be one mechanism linking racism and disease risk.

"We examined a biomarker of systemic aging, known as leukocyte telomere length," explained Dr. David H. Chae, assistant professor of epidemiology at the University of Maryland School of Public Health and the study's lead investigator. 

Shorter telomere length is associated with increased risk of premature death and chronic disease such as diabetes, dementia, stroke and heart disease. "We found that the African American men who experienced greater racial discrimination and who displayed a stronger bias against their own racial group had the shortest telomeres of those studied."

Telomeres are repetitive sequences of DNA capping the ends of chromosomes, which shorten progressively over time -- at a rate of approximately 50-100 base pairs annually. Telomere length is variable, shortening more rapidly under conditions of high psychosocial and physiological stress. 

"Telomere length may be a better indicator of biological age, which can give us insight into variations in the cumulative 'wear and tear' of the organism net of chronological age," said Chae. Among African American men with stronger anti-Black attitudes, investigators found that average telomere length was 140 base pairs shorter in those reporting high vs. low levels of racial discrimination; this difference may equate to 1.4 to 2.8 years chronologically.

Participants in the study were 92 African American men between 30-50 years of age. Investigators asked them about their experiences of discrimination in different domains, including work and housing, as well as in getting service at stores or restaurants, from the police, and in other public settings. They also measured racial bias using the Black-White Implicit Association Test. This test gauges unconscious attitudes and beliefs about race groups that people may be unaware of or unwilling to report.

Even after adjusting for participants' chronological age, socioeconomic factors, and health-related characteristics, investigators found that the combination of high racial discrimination and anti-Black bias was associated with the shortest telomeres. 

On the other hand, the data revealed that racial discrimination had little relationship with telomere length among those holding pro-Black attitudes. "African American men who have more positive views of their racial group may be buffered from the negative impact of racial discrimination," explained Chae. "In contrast, those who have internalized an anti-Black bias may be less able to cope with racist experiences, which may result in greater stress and shorter telomeres."

The findings from this study are timely in light of regular media reports of racism facing African American men. "Stop-and-frisk policies, and other forms of criminal profiling such as 'driving or shopping while Black' are inherently stressful and have a real impact on the health of African Americans," said Chae. 

Researchers found that racial discrimination by police was most commonly reported by participants in the study, followed by discrimination in employment. In addition, African American men are more routinely treated with less courtesy or respect, and experience other daily hassles related to racism.

Chae indicated the need for additional research to replicate findings, including larger studies that follow participants over time. "Despite the limitations of our study, we contribute to a growing body of research showing that social toxins disproportionately impacting African American men are harmful to health," Chae explained. "Our findings suggest that racism literally makes people old."

Constant Race-based Discrimination can Lead to 'Racial Battle Fatigue' for African-Americans

Date: March 4, 2011

Source: Penn State

Just as the constant pressure soldiers face on the battlefield can follow them home in the form of debilitating stress, African Americans who face chronic exposure to racial discrimination may have an increased likelihood of suffering a race-based battle fatigue, according to Penn State researchers.

African Americans who reported in a survey that they experienced more instances of racial discrimination had significantly higher odds of suffering generalized anxiety disorder (GAD) sometime during their lives, according to Jose Soto, assistant professor, psychology.

Generalized anxiety disorder has both psychological and physical symptoms that are so severe that they can significantly affect everyday tasks and job performance. People with the disorder may have chronic worrying, intrusive thoughts and difficulty concentrating. Physically, the disorder may manifest such symptoms as tension headaches, extreme fatigue and ulcers. Some of these symptoms are associated with "racial battle fatigue," a term coined by William A. Smith, associate professor, University of Utah.

"The results of our study suggest that the notion of racial battle fatigue could be a very real phenomenon that might explain how individuals can go from the experience of racism to the experience of a serious mental health disorder," said Soto. "While the term is certainly not trying to say that the conditions are exactly what soldiers face on a battlefield, it borrows from the idea that stress is created in chronically unsafe or hostile environments."

The researchers, who reported their findings in the current issue of the Journal of Anxiety Disorders, examined data from the National Survey of American Life, a study of 5,899 American adults. The study collected data on, among other topics, mental health and experiences of discrimination from 3,570 African Americans (60.5 percent of the total study population), 1,438 Afro-Caribbeans (24.4 percent) and 891 non-Hispanic Whites (15.1 percent).

Of the African Americans surveyed, more than 40 percent reported they experienced some form of racial discrimination, and approximately 4.5 percent reported suffering from GAD. About 39 percent of Afro-Caribbeans reported examples of racial discrimination, but only 2.69 percent had ever developed GAD.

The experience of racial discrimination, however, was not associated with GAD for Afro-Caribbeans. Soto, who worked with Nana Dawson, graduate student in psychology and Rhonda BeLue, assistant professor, health policy and administration, suggested that because Afro-Caribbeans have a different history from African Americans, they may both define and manage racial discrimination differently.

While non-Hispanic whites had higher rates of generalized anxiety disorder than both African Americans and Afro-Caribbeans, only 7.79 percent of non-Hispanic whites reported incidents of racial discrimination. Although experiences of racial discrimination among non-Hispanic whites were not associated with the development of GAD, experiencing other forms of discrimination, such as age and gender discrimination, was associated with the disorder.

"One interesting finding from the study is that non-racial discrimination seems to be associated with the development of GAD for all three groups in the sample," Soto said. "About 49 percent of non-Hispanic whites said they suffered other forms of discrimination." Soto said the connection between racism and severe anxiety underscores the negative impact that discrimination has on society.

"This is just one instance of how powerful social stressors can impact healthy functioning," Soto said. "And I would suspect, if we could wave a wand and eliminate racism from our past and our present, we would also eliminate a lot of health disparities."