Funding: the study was supported in part by the Russian Foundation for Basic Research (RFBR) grant together with the Government of the Chelyabinsk Region (Contract № 20-44-740007\20 of 28.01.2021), as well as by the Federal Target Program of FMBA of Russia “Modernization of Hightech Methods Aimed at Identifying Medical Consequences of Radiation Exposure in Personnel of the Mayak PA and the Population of the Ural Region” (code “Medical Consequences-21”).

Acknowledgments: the authors would like to express their gratitude to Savkova N.F., senior laboratory assistant, for technical and laboratory support.

Author contribution: Vozilova AV — study concept, research priority setting, literature review, manuscript writing; Krivoshchapova YaV — developing criteria for analysis, staining and slide assessment, statistics, manuscript writing.

Compliance with the ethical standards: the study was approved by the Ethics Committee of the Urals Research Center for Radiation Medicine (protocol No. 7 dated 20 October 2023); individuals, who were through cytogenetic testing, submitted the informed consent to blood sampling and further assessment.