Comparative analysis of epigenetic variability in two pine species exposed to chronic radiation in the Chernobyl and Fukushima affected zones

• Published in: Environmental pollution (1987) 2023-08, Vol.330, p.121799-121799, Article 121799
• Main Authors: Bondarenko, Vladimir, Geras'kin, Stanislav, Bondarenko, Ekaterina, Yoschenko, Vasyl, Bondarenko, Sergey, Khanova, Anastasiya, Garbaruk, Dmitriy, Nanba, Kenji
• Format: Article
• Language: English
• Subjects: Chernobyl and Fukushima accidents; Chernobyl Nuclear Accident; Chronic radiation exposure; DNA methylation And hydroxymethylation; Epigenesis, Genetic; Epigenetics; Fukushima Nuclear Accident; Pine; Pinus - genetics; Pinus sylvestris - radiation effects; Radiation Exposure; Radiation Monitoring; Transposable elements
• ISSN: 0269-7491; 1873-6424
• DOI: 10.1016/j.envpol.2023.121799

Comparative analysis of epigenetic variability in two pine species affected as a result of the Chernobyl and Fukushima accidents is presented. The absorbed dose rate within the affected Chernobyl sites varies over a wider range (1.5–24.6 μGy/h) than within the Fukushima sites (3.5–6.5 μGy/h). It was shown that chronic irradiation can change the level of whole genome methylation in pine populations, but in different ways. The genomes of Japanese red pines are hypomethylated, and the degree of methylation and hydroxymethylation decreases with an increase in the level of radiation exposure. In contrast, the percentages of genome methylation and hydroxymethylation in Scots pine populations exceed the reference levels. The observed discrepancy in the patterns of genome-wide DNA methylation can be attributed partly to the design of the study (differences in the climate, radiation dose, age and species of the pines) which could affect the results. In the frame of IRAP analysis, a larger number of different bands was observed in the Chernobyl populations compared to the Japanese populations. Both the Japanese and Chernobyl populations are characterized by significant genetic variability. However, the main part of this variability is observed within populations. The dendrograms, based on presence/absence of IRAP fragments and Nei's genetic distances, revealed subdivisions of the Chernobyl and Japanese populations according to the level of radioactive contamination. Analysis of the results presented will improve our understanding of the mechanisms underlying the responses of pine trees to chronic radiation exposure. [Display omitted] •Chronic irradiation can change the level of genome methylation in pine populations.•The genomes of Japanese red pines from contaminated sites are hypomethylated.•The genomes of Scots pines from contaminated sites are hypermethylated.•Chernobyl and Fukushima populations were clustered according to radiation exposure level.