Possibilities of application of DNA Comet Assay (literature review)

To ensure the sanitary and epidemiological well-being of the population, it is necessary to monitor the state of the environment. Today, there is a wide range of methods available for identifying factors that can adversly affect human health, including those capable of disrupting genetic structures in cells. One of the key tools in genotoxicology that enables the assessment of DNA damage at the level of individual cells is the comet assay. Since its introduction in the 1980s, this method has undergone significant modifications aimed at increasing its sensitivity, specificity, and versatility of application. This review outlines the principles and basic protocols of the method, discusses modifications of the classical comet assay; methods for improving detection capability of different types of DNA damage and assessment of repair processes. A search for relevant studies published in the databases Scopus, Web of Science, PubMed, Russian Research Citation Index, for the period 1984–2024 was performed. The review includes information from forty seven full-text sources.

Conclusion. The DNA comet assay is becoming an increasingly in-demand tool in research aimed at ensuring the sanitary and epidemiological well-being of the population, identifying environmental and industrial factors dangerous to the genetic health of the population, assessing the individual sensitivity of human cells to genotoxicants to determine risk groups and implement preventive measures. The development of new protocols involving DNA repair enzymes specific to particular types of damage, along with the use of fluorescent dyes, allows evaluating DNA damage and repair processes. The use of cryopreservation of whole blood and lymphocytes for subsequent DNA analysis enables large-scale, long-term epidemiological studies. Automating comet assay analysis using deep learning methods will improve the accuracy of identifying DNA damage types, which is essential for clarifying the mechanisms of action of specific substances.

Contribution:
Gorenskaya O.V. – data collection and analysis, writing and editing the text;
Demidova Yu.V. – data collection;
Kotnova A.P. – data collection;
Ilyushina N.A. – the study concept and design, data collection and analysis, writing and editing the text.
All authors are responsible for the integrity of all parts of the manuscript and approval of the manuscript final version

Conflict of interest. The authors declare no conflict of interest.

Funding. The study was carried out within the framework of the state task No. 121090800086-7.

Received: June 30, 2025 / Accepted: October 15, 2025 / Published: November 14, 2025

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