Effects of genomic instability in populations of Drosophila melanogaster from regions of Ukraine with different impact of radiation factors

Abstract

Purpose

To investigate differences in the gonadal dysgenesis frequency as one of the indicators of genome instability through natural populations of Drosophіla melanogaster, selected from Ukrainian regions with different radiation impacts. Follow-up study of the dynamics of this indicator under chronic exposure in laboratory conditions for 10 generations.

Materials and methods

The study was conducted in two stages. The first one included trapping of insects in regions with different radiation loads with subsequent assessment of both the time of maturation and the index of the gonadal dysgenesis through the first (F1) generation, obtained in laboratory conditions. At the second stage, the dynamics of this indicator were investigated for the F1-descendants of each ten consequent generations, which were developed under laboratory conditions both with and without additional gamma-exposure with different characteristics of the dose rate 1.2 × 10⁻⁸, 0.3 × 10⁻⁸ and 0.12 × 10⁻⁸Gy/sec.

Results

Differences in the gonadal dysgenesis frequency as one of the indicators of genome instability were revealed in F1-descendants of natural populations of Drosophіla melanogaster, selected from regions of different radiation impact. Under conditions of additional low rate chronic irradiation in laboratory conditions for 10 generations, significant differences in changes in the level and dynamics of this indicator were established depending on the accumulated dose of Drosophila populations from the city of Netishyn (Khmelnytskyi NPP) and Magarach city. There were no signs of adaptation.

Conclusions

The discrepancy between the real and expected biological effects has reflected the difference in the intensity of the radiation background, which was traditionally determined by the gamma-emitters and did not take into account the wide range of other genotoxic elements from nuclear power emissions. A complex, non-monotonic type of frequency dynamics of gonadal dysgenesis could be determined by the interaction of radiation damage, protection and recovery.

Keywords:

• Drosophila melanogaster
• ionizing radiation
• mobile elements
• gonadal dysgenesis
• genomic instability
• dynamic effects of chronic exposure

Acknowledgment

The authors are gratitude to DrSci I.A. Kozeretska and Ph.D. O.V. Protsenko, Taras Shevchenko Kyiv National University for both providing experimental material from Magarach, Lubny and Pyriatyn and discussing the results.

Disclosure statement

The authors have no conflict of interest.

Additional information

Funding

The study was conducted in the framework of funding for research of the National Academy of Sciences of Ukraine No. III-3-18, "Methods and algorithms for minimizing environmental risks."

Notes on contributors

Alexandra Kravets

Alexandra Kravets is the Head of the Department of Biophysics and Radiobiology in Institute of Cell Biology and Genetic Engineering of the National Academy of Science of Ukraine. She has published more than 200 papers and 6 monographs. Her area of expertise includes analytical methods of injected dose assessment and low dose effects.

Daryna Sokolova

Daryna Sokolova is a Senior researcher in the Department of Biophysics and Radiobiology in Institute of Cell Biology and Genetic Engineering of the National Academy of Science of Ukraine. She has contributed to 81 scientific publications in the field of molecular radiobiology and biotechnology. Her area of the expertise includes molecular genetics and molecular radiobiology as well as radioecology.