Whenever social scientists ask a question in a book title, especially a question about the power of science to achieve something, the answer is obviously “No.” Indeed, we do not have to wait long before the suspense is lifted. Margaret Lock and Gisli Palsson answer the question Can Science Resolve the Nature/Nurture Debate? with “The position we take is that science cannot resolve nature/nurture debates
In effect, such debates are a red herring because nature and nurture are not readily demarcated objects of scientific inquiry” (p. 10). At the end of the book, the authors add that such debates should not be resolved. The book, however, is not a red herring. Lock and Palsson take stock of developments in the science of epigenetics, and, to a lesser extent, in the overlapping field of the microbiome. These developments follow the disappointment with genetic deterministic thinking during the 20th and beginning of the 21st century and offer an opportunity to think through the role of nurture at the molecular level.
The book consists of two parts: a historical overview of epigenetics that traces its history over the past two centuries, mainly in Europe, and a set of critical observations offering warning signs to anthropologists of how epigenetics may reinforce a reductionist biological paradigm. The historical overview examines epigenetic thinking, both as a term and a historical body of thought, in evolving theories of biomedicine, procreation, and inheritance. We also receive a whirlwind review of the rise and fall of the gene as master molecule with stops at eugenics, Watson and Crick, the human genome project, and genetic anomalies calling into question the prima donna role of the gene. These surprising findings facilitated a revival of epigenetic thought centered on gene regulation rather than changes to the genetic code, specifically the mechanism of DNA methylation. Epigenetics creates space for nurture, both of internal and external environmental factors, and offers a more dynamic and interactive picture of a reactive genome.
While Lock and Palsson marvel at how this research meshes temporal dimensions from evolutionary time to life-course and seasonal changes, renders biological causality more contingent, and blurs our understanding of a unified self, their mission is to fire a warning shot. Reviewing some of the highlights of epigenetic research, the authors observe that epigeneticists tend to “miniaturize” (p. 98) nurture in order to standardize research practices and obtain accurate and statistically significant results. This may risk an insidious biological neo-reductionism—insidious because the highly anticipated environmental counterpart regulating the genome may be nothing more than a cellular process. Their argument is that epigenetics, with its renewed focus on environment and blurring of the genome and its entanglements, offers an opportunity to explore the accumulated toll of social injustice. Epigenetic science therefore should attend to history, politics, and social relations mired in poverty, violence, discrimination, and racism. They link this claim to the discussion of the Anthropocene, a geological epoch where humans are dominating the earthly ecosystem, and note again that the environmental deprivation disproportionately hurts the poor and disenfranchised.
Lock and Palsson expertly map ontological and epistemological shifts, and their exposé, if somewhat breezy, is thoughtful and insightful. They carry the mantle of cultural anthropology proudly, alerting readers that the social should matter. The key word, however, is “should,” because in spite of a blizzard of publications gesturing to epigenetics, precious few novel applications of epigenetics have emerged from the recent rounds of research. Biomedical researchers did not need an epigenetic paradigm to recommend folic acid during pregnancy or to screen for a disorder called phenylketonuria to prevent intellectual disabilities with dietary changes. Similar to the situation 15 years ago for genomics, we don’t know yet where the chips will fall in epigenetics, if at all. This short book should then be thought of as a gateway reading aimed at social scientists interested in the intersection of medical anthropology and science studies, illuminating the bright and blind spots of epigenetics.