Problems of Radiation Medicine and Radiobiology

Peculiarities of induction and persistence of hidden chromosome instability in peripheral blood lymphocytes of persons occupationally exposed to ionizing radiation

M. A. Pilinska, S. S. Dybsky, O. B. Dybska, L. I. Shvayko, V. O. Sushko
State Institution “National Research Center for Radiation Medicine of the National Academy of Medical Sciences of Ukraine”, Melnykov str., 53, Kyiv, 04050, Ukraine

Objective – to investigate the induction of hidden chromosome instability in persons occupationally exposed to ionizing radiation and its persistence in vitro in successive mitoses.
Materials and methods. Using two tests (“G2-bleomycin sensitivity assay” and two-term cultivation of human peripheral blood lymphocytes) voluntary cytogenetic examination of 15 individuals participated in the conversion of the “Shelter” (“Chornobyl NPP”) into ecologically safe system had been carried out. Total 24 034 metaphase had been analyzed, of which 12 243 – without additional mutagenic exposure, 11 791 – exposed to bleomycin in vitro at concentration of 0.05 μg/ml.
Results. The magnitude and dynamics of background as well as bleomycin-induced cytogenetic effects in both terms of lymphocytes’ cultivation in occupational group differed significantly from the group of comparison towards increasing of chromosome instability indices with significant interindividual fluctuations.
Conclusion. Interindividual differences in persistence of radiation-induced hidden chromosome instability in successive generations of human somatic cells had been found.

Key words: ionizing radiation, bleomycin, testing mutagenic exposure, hidden chromosome instability, persisting of cytogenetic effect in successive mitosis.

Problems of radiation medicine and radiobiology. 2014;19:321-333.