Study of the Telomere-telomerase System and the Expression of Candidate Genes in the Leukocytes of Patients With Depressive Disorder: Search for Peripheral Markers of Somatic Stress

Inclusion Criteria: * Persons who have given their written informed consent * absence of a diagnosis of major depressive disorder throughout the study and no history of psychiatric disorders * diagnosis of a first episode of a major depressive disorder * diagnosis of a recurrent major depressive disorder (at least three episodes) with or without resistance to therapy Remarks: * the diagnosis of major depressive disorder with characteristics of melancholy must be clearly mentioned in the case report form but is not a reason for not being included in the study * the presence of a recent or older attempted suicide must lead to a careful clinical assessment of the diagnosis of depressive disorder and must be clearly mentioned in the case report form. Exclusion Criteria: * Persons not covered by the national Health Insurance Agency * Psychotic or bipolar disorders * Severe personality disorders * cardiovascular disease, proven inflammatory disease and cancer * persons unable to give their consent personally, * persons in emergency situations, * pregnant women, * breast-feeding women