Precision of scoring radiation-induced chromosomal aberrations and micronuclei by unexperienced scorers

Abstract

Purpose: Dose assessment plays an important role in case of radiological accidents and can be performed by scoring structural changes of chromosome morphology induced in cells by ionizing radiation. The results of such a test are biased by scorer experience, therefore, simple to learn assays are recommended to be used when fast analysis of a large amount of data is needed. The aim of this study was to compare the performance of two radiobiological assays – chromosomal aberrations and micronuclei – by unexperienced scorers with the reference values generated by an expert.

Materials and methods: Each participant of an EU-funded two-week radiobiology course was asked to score Chinese hamster ovary cells exposed to gamma radiation up to 4 Gy. The congruence of students’ and expert’s scores at each dose and the coherence of the dose-response curve parameters between the students were investigated.

Results: Micronucleus test tended to be faster and easier to learn than scoring chromosomal aberrations. However, both assays carried out by inexperienced students showed reasonable dose-response curves.

Conclusions: In the case of a large radiological accident involving many casualties, the unexperienced scorers would support the process of biodosimetric triage by cytogenetic biological dosimetry.

Keywords:

• Chromosomal aberrations
• micronuclei
• ionizing radiation
• radiobiological assays

Disclosure statement

The authors report no conflict of interest. The authors alone are response for the content and writing of the paper.

Additional information

Funding

The work described in this paper has been partly supported by the European Commission, within the CONCERT project. This project has received funding from the Euratom research and training program 2014-2018 under grant agreement No 662287. MG, AT, JŻ and BBW were supported by the Polish Founds of Science.

The work described in this paper has been partly supported by the European Commission, within the CONCERT project. This project has received funding from the Euratom research and training program 2014-2018 under grant agreement No 662287. MG, AT, JŻ and BBW were supported by the Polish Founds of Science.

Notes on contributors

Maciej Gałecki

Maciej Gałecki is a PhD student at the Biomedical Physics Division, Faculty of Physics, University of Warsaw. His research area of interest is computer vision and machine learning applications in medicine and psychology. He is also committed to developing a tool that enables automatic analysis of images of cell colonies obtained in physical and biological experiments.

Adrianna Tartas

Adrianna Tartas is a PhD student at the Biomedical Physics Division, Faculty of Physics, University of Warsaw. Her main research area is Monte Carlo modeling to describe the processes of formation of repair foci as a result of various types of ionizing radiation on human cells.

Agata Szymanek

Agata Szymanek works as a bioinformatician in a Research and Development group of Ardigen, specializing in genomics and data analysis. She holds a double degree in Biotechnology and Applied Bioinformatics. During her engineering thesis, she was applying statistical methods for GWAS study in radiosensitivity, which led her to participate in the CELOD (cellular effects of ionizing radiation) course. She was also collaborating with the London School of Hygiene and Tropical Medicine, investigating the genetic background of parasitic drug resistance. Whilst working in the Cancer Center Amsterdam, she was conducting a statistical analysis on retinoblastoma patients’ transcriptomes, and she participated in numerous training opportunities, including both the European Bioinformatics Institute and the Netherlands Bioinformatics and Systems Biology research school courses. Currently, she is working in the field of genomics and human microbiome research.

Emma Sims

Emma Sims is a PhD student at Cranfield University and part of the Bioinformatics Group in Agrifood. She holds degrees in Computer Science, Mathematics, and Applied Bioinformatics; specializing in statistics, machine learning, and software development. Previously she has developed an R package which can simultaneously analyze and compare various modeling techniques for a range of proteomics input data. Her current projects involve developing pattern recognition algorithms within images, and developing cloud computing web platforms to analyze the metabolomics data of fresh food items.

Lovisa Lundholm

Lovisa Lundholm, PhD, is a researcher in the field of radiation biology at the Stockholm University. She has a background within molecular biology and cancer research. Her work focuses on the impact of chromatin condensation on the response of cells to radiations of different qualities.

Alice Sollazzo

Alice Sollazzo defended her PhD in Molecular Bioscience, Radiobiology, in 2017 at The Department of Molecular Biosciences, The Wenner-Gren Institute (MBW), Stockholm University, Stockholm Sweden. Her work focuses on gaining new insight on the molecular mechanisms behind the repair of DNA damage caused by exposure to mixed- fields of low and high LET radiation.

Lei Cheng

Lei Cheng is a PhD student in the field of radiation biology in the Department of Molecular Biosciences, The Wenner-Gren Institute (MBW) at the Stockholm University. Cheng focuses on studying the cellular effects of combined exposure to radiations of different qualities.

Yohei Fujishima

Yohei Fujishima, M.Sc., is a PhD student in Department of Radiation Biology, Institute of Radiation Emergency Medicine (IREM/HU), Hirosaki University. His research field is cytogenetic biodosimetry including optimizations and developing methodologies of blood culture for biodosimetry.

Mitsuaki A. Yoshida

Mitsuaki A. Yoshida, PhD, is a professor at the Department of Radiation Biology, Institute of Radiation Emergency Medicine (IREM/HU), Hirosaki University. His professional fields are molecular cytogenetics including chromosome analysis by banding methods and chromosome dose assessment in the radiation exposure accident. Also, he is contributing to the establishment of the system for preparedness and response of radiation emergency medicine. After the accident at the Fukushima Nuclear Power Station due to the 2011 East Japan great earthquake, he continues to support Fukushima using the chromosome analysis method in order to investigate the effect of radiological substances released from Fukushima Dai-Ichi NPP. He is also a member of WHO BioDoseNet and the Chromosome Network Council in Japan.

Jarosław Żygierewicz

Jarosław Żygierewicz, PhD, is an Assistant Professor at the Biomedical Physics Division, Faculty of Physics, University of Warsaw. His research interests concern time-frequency analysis of EEG and MEG signals. He developed methodology for statistical analysis of event related synchronization and desynchronization in EEG and MEG. He is involved in designing brain computer interfaces, validation of psychological models of emotions and working memory. His research encompasses also exploratory data analysis.

Andrzej Wojcik

Andrzej Wojcik, PhD, is professor of radiation biology at the Stockholm University. He focuses on studying the cellular effects of radiation, with special focus on combined exposure to radiations of different qualities. He is also interested in developing and validating cytogenetic tools for biological dosimetry.

Beata Brzozowska-Wardecka

Beata Brzozowska-Wardecka, PhD, works in the Biomedical Physics Division at Faculty of Physics, University of Warsaw and her scientific interests concern medical physics, radiobiology in particular. She joined the mixed beam effect for cancer risk project at Stockholm University. She now works with PARTRAC codes (in cooperation with W. Friedland, Helmholtz Center) to model DNA damage and repair in cells exposed to ionizing radiation.