Marked by the Past

The following is a guest blog post by Sarah Abel, author of Permanent Markers: Race, Ancestry, and the Body after the Genome.

Over the past twenty years, DNA ancestry testing has morphed from a niche market into a booming international industry that encourages members of the public to answer difficult questions about their identity by looking to the genome. At a time of intensified interest in issues of race and racism, the burgeoning influence of corporations like AncestryDNA and 23andMe has sparked debates about the commodification of identity, the antiracist potential of genetic science, and the promises and pitfalls of using DNA as a source of “objective” knowledge about the past.

This book engages these debates by looking at the ways genomic ancestry testing has been used in Brazil and the United States to address the histories and legacies of slavery, from personal genealogical projects to collective racial politics.


Commercial DNA ancestry testing first became available to the public just over two decades ago. In various American and European countries these scientific-looking reports – typically expressed as a series of maps and percentages, linking clients to living human “reference” populations around the world – have been presented as a way for individuals to delve into their “unique” ancestral genetic makeup. From the very start, these claims have raised debates about the relationship such technologies establish between genetics and identity. For advocates of these techniques, DNA testing can provide deeper, more objective insights into identity than “superficial” and “divisive” racial, national, and ethnic categories; for critics, it is “junk science,” of little value to personal identity quests.

In Permanent Markers: Race, Ancestry, and the Body after the Genome, I explore how the recent rise in popularity of DNA ancestry testing is impacting notions of race, ancestry, and identity in Brazil and the United States. These two countries are notorious for their apparently divergent approaches to race: Brazil is thought of as “the country of racial mixture,” whereas the United States remains famous for its historical “colour line.” Both continue to grapple with the legacies of slavery and colonialism and the ongoing realities of racism, and both have turned to genetics in search of alternative ways of thinking about ancestry and their collective pasts. The title I chose for the book, Permanent Markers, reflects an apparent paradox: while genetic data are often used to try and cut through racial paradigms and uncover deeper truths about our pasts, these technologies can also reinforce the idea that “race” is hardwired into our very genetic makeup. Why does this happen? 

One way of thinking about this is to imagine the rings you see when you look at a cross section of a tree trunk – this is the imagery I have used on the cover of my book. The rings are the result of the tree’s growth pattern over a given period of time, a process that can be conditioned by climate and other environmental factors, but also by human activities, for instance forest fire or air pollution. Trees also accumulate cracks and fractures – other kinds of marks that may be signs of stress or blight. If they know what they are looking for, scientists can use these diverse marks to reconstruct not only the history of a single tree, but the events that shaped the life of an entire forest. However, interpreting these events requires a critical eye and contextual knowledge – otherwise, we might assume these marks are simply an inherent part of the tree’s “natural” life processes.

In a similar way, the genetic mutations or “markers” used to produce DNA ancestry reports can be read as the residue of histories of migration and sexual reproduction. Under regimes of slavery and colonialism, sex and forced migrations were used to reproduce forms of “racial” difference, as a way of maintaining the colonial order. In this sense, the race-like structures we can see in DNA ancestry portraits should be understood not as innate features of our genetics, but as the biological imprint of the racialized ideologies and structures of domination that have governed societies like Brazil and the United States for generations. My book centres, then, on a biocultural conception of race as “biology-managed-by-culture,” and in that sense I follow on from other anthropologists like Jada Benn Torres, Gabriel Torres Colón, Jean-Luc Bonniol, Peter Wade, Gísli Pálsson, among others, who have used similar approaches in their work on genetics from social perspectives. This is not the only way that racial regimes act upon our bodies and our psyches – for instance, some social epidemiologists have argued that structural, institutional, and interpersonal forms of racism experienced during a person’s lifetime, or over several generations, can have significant effects on a person’s health outcomes, including the incidence of certain diseases and rates of premature mortality. Race and racism are therefore multidimensional phenomena that have various embodied, psychological, and social effects, which shape us both on the individual and societal level. 

The title, Permanent Markers, is also meant as a provocation: will there come a time when race is no longer a salient marker of inequality, or identity? What would need to happen for this to be the case? Is it necessarily desirable or progressive to replace social conceptions of race with genetic paradigms of difference? How else might we use genetic data to reconstruct aspects of our pasts that have been obscured by racism and processes of racialization? In addressing these questions, Permanent Markersinvites readers to explore how genetic ancestry data might be read critically, against the grain, to yield more nuanced understandings of these complex pasts.


Sarah Abel is British Academy Postdoctoral Fellow at the University of Cambridge’s Centre of Latin American Studies.