Bringing together epigenetics and social epidemiology
Our culture still has't integrated these two independent domains of knowledge. And yet, as soon as we consider them in relation with one another, they spring a distant early warning we definitely ought to be aware of. It allows us to understand, for example, why a population's health does not mirror its degree of economic development, but rather depends on how good its individuals' intimate life-shaping environments have been to create favorable epigenetic imprints on these individuals' genomes during their primal lives [12].
1. The quality of our surroundings determines the way our DNA is used. True, our personal genetic heritage is set at conception. But from this very moment on, our whole life is shaped by our DNA’s environment. From its innermost circles (intranuclear, cytoplasmic, interstitial) to its more distant ones (maternal, paternal, social), events of all kind, intensity and duration are constantly adjusting the degree of activity and/or inhibition of each and every element of our genome through epigenetic processes [13, 14]. The earlier these founding events ("experiences" or "lack of experiences") occur over our embryonic, fetal and postnatal developments, the more they determine who we shall be [15, 67].
2. DNA's surroundings. Be that as it may, a former saying like “DNA makes the person” must definitely be put aside. It is no less absurd than would be the claim: “the watercolor box makes the picture”. Because from the very beginning it's the watercolor box’s environment that makes the picture. Exactly as the complex DNA's environment uses the DNA to build the person, the painter – a very complex environment indeed – uses the boxed set of pigments to build the picture. Note that the infinite variety of interrelated elements, spanning from the painter's sensorial and affective motivations (at the very moment he starts conceiving the picture) to his whole life of sensorial, affective and social experiences from which his personality, sensibility, skills and general motivations have resulted, largely matches the complextiy of any DNA's surroundings.
3. Social-epidemiology reveals that inequality is bad for everyone: Wilkinson & Pickett’s finding that financial inequality and health indices are negatively correlated in developed countries [16] raised the question: why? Lack of access to medical care – mostly for people with small incomes – appears not to be a satisfactory explanation [17]. The current hypothesis is that inequality in a rich community is responsible for a societal stress that negatively affects everyone, rich or poor [18], old or young, with multiple consequences on health and social behavior [16,19, 20, 21].