Sex and gender in the era of epigenetics Female/male parity and “gender theory” are constant subjects of debate, yet the body is largely overlooked. In effect, certain illnesses mainly affect women and other men. Gender-linked differences (GLD) have a genetic and epigenetic basis – at the interface between genes and the environment – as well as hormonal basis. However, women are under-represented in the clinical essays, and females sometimes absent from animal studies; this results in diagnoses and treatments that are less well adapted and in twice as many secondary health troubles in women. Why is there such a disparity? It is certainly ignorance, or denial, of GLD that is at the origin of this inegality and not the GLD themselves. It is not by covering them up that these descriminations will be eradicated in the domain of health.