Unfortunately, it is not easy–even in principle–to separate these issues neatly. For example, those who cling to genetic essentialism dismiss environmental causation as largely incidental or beside the point. Even ‘epigenetics’ is too close to environmental causation to be acceptable. True enough, like many things in today’s world of science (indeed, probably always typical of human affairs), we have fads and current epigenetic studies are in part just that–a way to get grants, get papers in the ‘name’ journals and get news attention.
However, epigenetics refers to the means by which gene expression is regulated. Cells are always sensing their environment in various ways that lead to modification of their chromosomes that controls which genes are used and which are shut down. In that very fundamental sense, every trait is an epigenetic trait. Indeed, a given gene’s ‘environment’ includes what’s going on in the rest of the genome in that same cell. The nontrivial scientific questions concern when, where, and how epigenetic mechanisms are at work in some context of interest–how the environment affects gene usage and its results.
Read the full, original story: Insanity: genes ‘versus’ environment as causes