Epigenesis for epidemiologists: does evo-devo have implications for population health research and practice?

Epidemiologists engage with a wide range of other disciplines, as reflected in many of the topics that would now be considered essential for any comprehensive grounding in the subject. Thus, ‘‘lifecourse’’ was a word I was only familiar with from sociological writings when I was completing an epidemiology master’s degree at the London School of Hygiene and Tropical Medicine a quarter of a century ago, but now there are Lifecourse Epidemiology research units, a plethora of textbooks, and diagnosticos of the health situation from national and international agencies often appeal directly to the notion. Socio-economic inequalities in health were of more interest to political activists than to academic epidemiologists, but (perhaps in the spirit of Herbert Marcuse’s ‘repressive tolerance’) are now an utterly mainstream concern. Psychological notions are pervasive, and some debates in the field have pitted primarily social notions of disease origins against more psychologically inclined approaches, bypassing traditional epidemiological explanatory frameworks. From econometrics, our discipline has imported instrumental variables analyses, among other borrowings. Genetics used to seem so distant from epidemiological concerns that, shamefully, during recruitment of participants for one of the studies I was involved with, I threw away large volumes of buffy coats from which DNA could have been extracted. Developmental biology became of greater epidemiological concern with the seminal studies of David Barker’s group on indicators of fetal growth and later life health outcomes. More recently, epigenetics has come to the fore and it is now unimaginable that a referee’s report would state ‘I do not know what the term epigenetics means’, a sentence included in a BMJ review I received when I included the term in a 1997 submission. In the current context, the excellent short book by Patrick Bateson and Peter Gluckman, Plasticity, Robustness, Development and Evolution (henceforth PRDE), which the authors précis for IJE readers, must be seen as dealing with issues of considerable concern to epidemiologists. The IJE published Patrick Bateson’s early exposition of the epidemiological relevance of some of the ideas in the book and also the first review of epigenetic epidemiology. Recent developments at the intersection of developmental and evolutionary biology—now generally given the moniker evo-devo—are covered in this book, and implications for human health and disease are touched upon. Here I am not going to outline the contents of the book, since this has been done by the authors, rather I will discuss several issues of particular relevance for epidemiologists and other public health scientists.