ESTIMATION OF SOMATIC GENE MUTAGENESIS IN PATIENTS WITH BENIGN TUMORS LIVING IN RADIATION CONTAMINATED REGIONS WITH DIFFERENT ¹³⁷CESIUM DENSITY

Abstract

The aim of this study was to compare the level of somatic mutagenesis in women with benign tumors of the reproductive system living in radiation contaminated regions of the Russian Federation with that in unexposed healthy individuals. Frequency of peripheral blood lymphocytes bearing mutations at T-cell receptor (TCR) locus was assessed by flow cytometry in 219 patients with myoma who had been living in Novozibkovskiy, Klintsovskiy districts of Bryansk region and Uzlovaya district of Tula region for 17-19 years since the moment of the Chernobyl accident. Mean ¹³⁷Cs densities in these districts were 708, 322 and 171 kBq/m² accordingly. The control group included 42 age-matched unexposed healthy individuals. There was no significant elevation in the TCR mutant cell frequency in patients from Uzlovaya district which was contaminated with radionuclides at low level in comparison to controls. The frequency of the TCR-mutant cells was significantly higher in patients from the most contaminated district (Novozibkovskiy and Klintsovskiy) as compared to the control group by Mann-Whitney test (p<0.05). Median values were 4.3˙10^-4, 5.9˙10^-4, 3.8˙10^-4 accordingly. However, only 19% of the patients had the TCR–mutant cell frequencies exceeding the 95% confidence interval in the control group (>7,0˙10^-4). The frequencies of mutant cells in other patients corresponded to those in the control group. Our results confirm that the TCR–method may be used for individual assessment of long-term health consequences after irradiation. Individuals with elevated TCR-mutant cell scores might belong to a high-risk group potentially prone to the development of neoplasm and need more thorough medical observation than the rest of population.