Genomics, Health Disparities, and Missed Opportunities for the Nation’s Research Agenda

Abstract

The completion of the Human Genome Project occurred at a time of increasing public attention to health disparities. In 2004, Sankar and colleagues 1 suggested that this coincidental timing resulted in an inappropriate emphasis on the contribution of genomics to health disparities, conflating racial patterns of disease with genetic ancestry, and distracting attention from the large and compelling body of scientific evidence pointing to social determinants of health disparities. 2 For example, genomic research has emphasized discovery of genetic contributors to diabetes risk, but the recent increase in the prevalence of obesity and type 2 diabetes, which disproportionately affects minority populations, cannot be attributed to genetic changes and rather reflects social forces affecting diet, food access, and patterns in physical activity. The introduction of new genomic health technologies could also exacerbate disparities in access to high-quality health care, if specific genomic testing improved health and was only available to those who were affluent. Nonetheless, the claim persists that genomic research can reduce health disparities-if only participation by minority populations in genomic research could be increased. 3 The source of this claim is an idiosyncratic usage of the term health disparities that may result in missed opportunities for the nation's health research agenda. Health disparities are generally understood to refer to systematic differences in health effects resulting from social disadvantage, but the term is often used in genomics to refer to differing health outcomes associated with population genetic variation. This usage arguably stems from the US focus on the association of health disparities with race/ethnicity (vs socioeconomic status), together with a growing body of knowledge about population genetic variation. Compounding the problem is a tendency in the United States to conflate health disparities and health care disparities, perhaps based on the erroneous assumption that improved health care will resolve health disparities. 4 The misunderstanding about the causes of health disparities leads to confusion about fruitful lines of research and potential remedies.A causal association between social position and health is well established. 5 This association has been documented in both developed and developing countries and dates back to the earliest records, despite substantial change over time in the principal causes of disease. A broad array of health conditions across the lifespan follows a social gradient, wherein better health and longer lifespans track with increases in social advantage. This pattern holds whether measured by proxies of social class, such as education, income, and occupation, or by race/ethnicity. 5 In the United States, health disparities are significant and widening and have attracted

Racial disparities in bipolar disorder treatment and research: a call to action

“…Kashyap and colleagues note that, although the role of genomics in health disparities is quite complex, it is critical to understand how genetic variation influences the health and well‐being of at‐risk communities to eliminate health disparities in the USA . On the other hand, West et al . argue that clarification of genetic contributors to disease etiology will not help to provide ways to address disparities, as they are rooted in social, material, and environmental conditions.…”

The Use of Racial Categories in Precision Medicine Research

“…Shawneequa L. Callier, JD, MA 1,2 Scholars have shown that promoting diversity and inclusion in precision medicine research is important for ethical and scientific reasons. The processes for classifying the populations that enroll in biomedical research, however, are often unclear, inconsistent, and poorly justified.…”

“…Genomic approaches, however, are insufficient to address the various social experiences that often correlate with poor health. 2 Discrimination in housing and employment, inadequate access to health insurance, and implicit and explicit biases in medical care, for example, substantially impact health outcomes, long-term health, and health disparities. 3(p135),4(p38) For these reasons, precision medicine studies that measure the effects of social, cultural, and environmental influences on health are essential to improve health outcomes.…”

Two Threats to Precision Medicine Equity

“…The arguments of genetic determinists obscure the hard work of parsing apart the true impact that genetic differences may have on population health, 35 and instead rest on a presumed understanding that "from both an objective and scientific (genetic and epidemiologic) perspective there is great validity in racial/ethnic self-categorizations, both from the research and public policy points of view." 23 The threat to precision medicine this view represents includes an oversimplification of diagnostic and therapeutic decisions that will be imprecise and inaccurate.…”