[Structural changes in the chromosomes of the peripheral blood lymphocytes of monkeys subjected to daily long-term irradiation].

During the period that lasted from 4 to 11 years after the cessation of the long-term daily gamma-irradiation the frequency of chromosome rearrangements in peripheral blood lymphocytes of monkeys exceeded the control level. The number of rearrangements did not change significantly at different total irradiation dosses (from 826 to 3677 r). The main type of structural chromosome rearrangements were symmetrical chromosome exchanges. Abnormal cell clones in peripheral blood lymphocytes of monkeys irradiated at low doses had no selective advantages during the periods of investigation.