Radiation-induced changes in DNA methylation and their relationship to chromosome aberrations in nuclear power plant workers

• Published in: International journal of radiation biology Vol. 91; no. 2; pp. 142 - 149
• Main Authors: Lee, Younghyun, Kim, Yang Jee, Choi, Young Joo, Lee, Joong Won, Lee, Sunyeong, Cho, Yoon Hee, Chung, Hai Won
• Format: Journal Article
• Language: English
• Published: England Informa Healthcare 01.02.2015; Taylor & Francis
• Subjects: Adult; Aged; Case-Control Studies; chromosome aberrations; Chromosome Aberrations - radiation effects; DNA methylation; DNA Methylation - radiation effects; Humans; Male; Middle Aged; nuclear power plant workers; Nuclear Power Plants; Occupational Exposure - adverse effects; Radiation; Repetitive Sequences, Nucleic Acid - genetics; nuclear power plant workers; DNA methylation; chromosome aberrations; Radiation
• DOI: 10.3109/09553002.2015.969847
• ISSN: 0955-3002; 1362-3095

Abstract Purpose: We investigated the association between occupational radiation exposure and DNA methylation changes in nuclear power plant workers. We also evaluated whether radiation- induced DNA methylation alterations are associated with chromosome aberrations. Materials and methods: The study population included 170 radiation-exposed workers and 30 controls. We measured global, long interspersed nuclear element-1 (LINE-1), and satellite 2 methylation levels in blood leukocyte DNA. The analysis of chromosome aberrations was performed on peripheral lymphocytes. Results: Global DNA methylation levels were lower in radiation-exposed workers than in controls. The methylation levels were negatively associated with the recent 1.5-year radiation dose in a multiple linear regression model (β = − 0.0088, p ≤ 0.001); the levels increased proportionally with the total cumulative dose in radiation-exposed workers. LINE-1 methylation levels were higher in radiation-exposed workers than in controls and were significantly associated with the total cumulative radiation dose in a multiple linear regression model (β = − 0.031, p = 0.035). Global DNA methylation levels were also correlated with chromosome aberrations among workers. Workers with low global methylation levels had a higher frequency of chromosome aberrations than did subjects with high global methylation levels. Conclusion: Occupational exposure to low-dose radiation could affect DNA methylation levels, and the radiation-induced DNA methylation alterations may be associated with chromosome aberrations.