Radiosensitivity and transgenerational effects in non-human species
Résumé
The ALLIANCE working group on effects of ionising radiation on wildlife brings together European researchers to work on the topics of radiosensitivity and transgenerational effects in non-human biota. Differences of radiation sensitivity across species and phyla are poorly understood, but have important implications for understanding the overall effects of radiation and for radiation protection: for example, sensitive species may require special attention in monitoring and radiation protection and differences in sensitivity between species also lead to overall effects at higher levels (community, ecosystem), since interactions between species can be altered. Hence, understanding the mechanisms of inter-species radiation sensitivity differences may help us understand mechanisms underpinning intra-species variation. Differences of sensitivity may also only be revealed when organisms are exposed to ionising radiation over several generations. This issue of potential long-term or hereditary effects for both humans and wildlife exposed to low doses of ionising radiation is a major concern. Animal and plant studies suggest that gamma irradiation can lead to observable effects in the F1 generation that are not attributable to inheritance of a rare stable DNA mutation. Several studies provide evidence of an increase of genomic instability detected in germ or somatic cells of F1 from exposed F0 organisms. This can lead to an induced radiosensitivity and can result in phenotypic effects or lead to reproductive effects and teratogenesis. In particular, studies are conducted to understand the possible role of epigenetic modifications such as DNA methylation, histone modifications or expression of non-coding RNAs in radiosensitivity as well as in adaptation effects. As such, research using biological models in which the relative contribution of genetic and epigenetic processes can be elucidated is highly valuable.