Finding the global in the local: Constructing population in the search for disease genes

Since the birth of genetics in the early twentieth century, geneticists have been keen to understand what their science can say about how humans differ from one another, including how they differ from one part of the globe to another. But the past twenty-five years or so have seen a notable surge in initiatives aiming to describe and analyse the genetic make-up of people living outside Europe and North America. Some of these initiatives profess a primarily anthropological orientation, aiming to capture and document as much as possible of the sheer diversity of human genetic constitutions: the Human Genome Diversity Project and National Geographic’s Genographic Project are cases in point. Other initiatives—often framed in terms of documenting genetic “variation” rather than “diversity”—claim a more practical orientation towards identifying gene variants of medical significance: the International Haplotype Mapping (HapMap) Project and the African Genome Variation Project exemplify this latter approach to human genetics. In explaining the medical value of such work, advocates commonly state that it will generate genetic information which will help to combat illness and foster health in the countries under study. Thus the International HapMap Project is framed in terms of the “need to be inclusive in the populations that we study to maximize the chance that all people will eventually benefit from this international research effort” (NIH News Advisory, 2002); while the African Genome Variation Project is presented as a step towards “provid[ing] a comprehensive resource for medical genomic studies in Africa” (Gurdasani et al., 2015, p. 331).In this chapter, I look beyond such professions of intent to examine a broader set of drivers that have structured the global expansion of genomic research and that skew how its findings are used. I show how recent initiatives to document the genetic constitution of people living in the world’s poorer regions have actually grown out of, and serve the purposes of, efforts to identify genetic factors which influence the health of people living predominantly in the global North. This is perhaps unsurprising. For one thing, most research into the genetics of disease and ill health has been conducted by researchers based in the wealthiest countries of Europe and North America. For another, such research is to a significant extent driven by commercial interests, in the hope of profiting financially from any resulting medical innovations; consequently, research has tended to focus on understanding the ailments affecting those sections of the world’s population that are most likely to be able to afford such innovations. In which case, why the recent turn to study the genomes of people living outside these rich regions? This chapter sets out to answer this question through a historical study of the changing aims and methodologies of medical genetics and human population genetics, and their recent convergence around new approaches to identifying genetic causes of ill health and disease.