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Methods of Classical and Molecular Cytogenetics Suitable for Biodosimetry of Persons with Professional Exposure to Carcinogens.

BACKGROUND
People in the health professions and other occupations are frequently exposed to carcinogens, including chemicals, cytostatic agents, and ionizing radiation with carcinogenic potential. These individuals require monitoring of their exposure, as well as biomonitoring for cytogenetic alterations. Classical and molecular cytogenetic methods can establish functional remedial measures, while preventing the emergence of malignant tumors as an occupational disease.


PURPOSE
This article presents the main principles, advantages, and limitations of classical cytogenetic and modern molecular cytogenetic methods. These include conventional cytogenetic analysis of chromosomal aberrations in peripheral lymphocytes of individuals exposed to chemical carcinogens and examination of sister chromatids and micronuclei after exposure to ionizing radiation. More recent methods include radioactive and fluorescence in situ hybridization, colour variants of the latter, comparative gene hybridization, spectral karyotyping, and the latest microchip methods.


CONCLUSION
Molecular cytogenetic methods make possible the refinement of methods used in the biomonitoring of chemicals and radiation. Their benefits include higher speed, automation of some processes, high sensitivity, focus on stable genetic changes capable of triggering the carcinogenesis process, and the possibility of determining deviations in non-dividing cells. Their disadvantages to date include lack of analysis of large numbers of individuals undergoing preventive examinations, undetermined norms or limit values for exposed individuals and work teams, and higher costs of examination. This work was supported from the program project of the Agency for Health Research of the Czech Republic with registration number P09-15-33968A with the fi nancial support of the Ministry of Health. The authors declare they have no potential conflicts of interest concerning drugs, products, or services used in the study. The Editorial Board declares that the manuscript met the ICMJE recommendation for biomedical papers. Submitted: 15. 10. 2018 Accepted: 4. 7. 2019.