[The results of 25 year-cytogenetic investigation of survivors exposed to different doses of irradiation in the Chernobyl accident].

Changes of registered levels of chromosome aberrations were studied in the peripheral blood lymphocyte cultures of 74 patients irradiated as a result of the Chernobyl accident by the instrumentality of the routine method during 25 year. The initial dose estimations by average dicentrics frequency varied from 0.2 to 9.8 Gy On the whole, the model of a double exponential type was the most adequate for the quantitative description of elimination of cytogenetical indices associated with different types of unstable chromosome aberrations. High individual variability of the elimination rate of chromosome aberrations and its dependency from the value of originally evaluated dose were discovered in the first period. The computer method of retrospective dose estimation was developed on the basis of this material. The method is based on the analysis of cell distributions in accordance with the number of dicentrics and as a whole, unstable chromosome aberrations, contained in them. In addition the dynamics of translocation frequencies in the peripheral blood lymphocyte cultures of a number of patients from this contingent was investigated starting from 10 years after irradiation by the instrumentality of FISH-method of chromosome staining.