RESUMO
The frequencies of somatic mutations at loci of glycophorin A (GPA) and T-cell receptor (TCR) were determined in control unexposed donors and Chernobyl clean up workers, who received low doses of irradiation up to 0.25 Gy. High variability of mutant rates for two investigated genes was shown in the clean up workers. No significant difference in the GPA (NO) mutant frequencies was observed between the clean up workers and control donors (p > 0.05), though there is a tendency for increasing the GPA mutation rate in the clean up workers. Meanwhile, the TCR mutation rate was significantly increased the clean up workers (p < 0.01), perhaps because of acceleration of spontaneous mutagenesis and possible genome instability. Persons with elevated levels of mutations at two loci can present a group at high risk in respect to oncological diseases.