Chromosomal mutagenesis in human somatic cells: 30-year cytogenetic monitoring after Chornobyl accident.

In the lecture we have generalized and analyzed the data of cytogenetic laboratory of National Research Center for Radiation Medicine of the National Academy of Medical Sciences of Ukraine on 30-year selective cytogenetic monitoring among the priority contingents of different ages exposed to radiation after Chornobyl accident in Ukraine. It is highlighted that not only targeted but also untargeted radiation-induced cytogenetic effects should be explored, especially in delayed terms following radiation exposure. The new methodical approaches for studying "bystander effect", individual radiosensitivity, and various forms of radiation-induced chromosomal instability (delayed, hidden, transmissible) have been proposed.

[Comparison of the possibilities of micronuclear and chromosomal aberration tests for evaluation of the effects of radiation of different intensities].

The comparative evaluation of sensitivity and specificity of the micronucleus and chromosome aberration tests for human lymphocytes at the delayed terms after acute exposure to high-dose as well as during constant exposure to low-dose gamma-radiation has been done. Accordance between these tests registered only in the cases of acute radiation sickness of second and third degrees of severity (irradiation doses above 200 cGy). Unspecificity of micronucleus test for estimation of the radiation load under constant low-intensity irradiation was found.