Genealogical and cytogenetic analysis has been carried out in 114 children with depressive disorders (DD), aged 7 to 17 years. Statistical treatment: SPSS Statistics 17.0.

The main objective was to study familiar and cytogenetic risk factors of DD in children.

A hereditary burden on mental diseases has been registered in 66.0 %, and on DD in 56.0 % of the families under investigation. Family accumulation of mental and noninfectious diseases in the genealogy of patients with DD has been established in the study. Hereditary transmission of pathological symptoms in a number of generations of probands with depressive disorders took place 1.8 more often on the maternal than on the paternal line, and it was 3.6 more frequent than on both lines simultaneously. A sevenfold increase in the spontaneous level of chromosomal aberrations has been registered in our patients as compared with their healthy age-mates, indicating destabilization of the genome in probands with the disease. A significant rise in chromosomal anomalies level, related with gender, age, type of the disease and hereditary burden on mental diseases, has been registered in patients with depression. Some informative prognostic symptoms for revealing persons of high risk as regards disorders in the chromosomal apparatus in children and adolescents with depressive disorders have been defined. The effectiveness of the proposed prognostic signs comes to 84.8%.