Clinical experience shows that, even in front of organic diseases, the sole reference to anatomy, physiology or even genetics does not suffice to make us understand our patients' sufferings. To apprehend the essence of such sufferings, we need to consider that the anatomic, physiologic, real body gives rise to another body, an imaginary body that, from primordial helplessness, constitutes itself through the relationship to another human being. According to this process, children constitute their subjectivity to become desiring, social beings in the culture. The dissociation between the anatomical, physiological body and the imaginary body institutes a fission through which subjectivity fades away, paving the way for the melancholic experience. This perspective shows that the sickening process encloses an identifie at o ry and intersubjective dimension. An individual's sickness necessarily affects the family cluster through the "genealogization " of both the symptom and the reshuffling of the trans generational representations. It is thus crucial that such experiences be taken into account to understand that the real genetic risk, revealed by science, is crosscut by the real-life experiences of an imaginary risk which determines both the individual and social representations, and even, in some cases, the possibilities of manifestation as well as the course of any disease.