Autoimmune diseases group together less than a hundred different clinical entities which are for the most part rare pathologies but which, in combination, concern 5-8% of the adult population with a strong female predominance (FAI²R: the disease chain rare autoimmune and auto-inflammatory drugs, fai2r.org). The common denominator of all these diseases is based on the breakdown of self-tolerance which is the origin of self-reactivity and whose physiopathological mechanisms are still not fully understood, which generates numerous cross-sectional or fundamental studies. In addition to this complexity, there are significant inter-individual variabilities which lead to the definition of subgroups of patients on the basis of the clinical-biological profile and / or the response to treatments. Consequently and in view of the need to establish the diagnosis early and then to propose the best treatment in the perspective of an individualized medicine, the clinical, biological and genetic characteristics of these subgroups of patients must be explored in order to improve diagnostic and therapeutic capacities.
