LET dependence of yield ratios of radiation-induced intra- and interchromosomal aberrations in human lymphocytes

• Published in: International journal of radiation biology Vol. 74; no. 1; pp. 17 - 25
• Main Author: SCHMID, M. BAUCHINGER E.
• Format: Journal Article
• Language: English
• Published: London Informa UK Ltd 01.07.1998; Taylor & Francis
• Subjects: Alpha Particles - adverse effects; Biological and medical sciences; Chromatin. Chromosome; Chromosome Aberrations - genetics; Chromosome Breakage - genetics; Chromosomes - radiation effects; Dose-Response Relationship, Radiation; Fundamental and applied biological sciences. Psychology; Gamma Rays - adverse effects; Humans; Linear Energy Transfer - genetics; Lymphocytes - radiation effects; Molecular and cellular biology; Molecular genetics; Neutrons - adverse effects; Protons - adverse effects; X-Rays - adverse effects; Chromosomal aberration; Exchange; Occurrence frequency; Radiation injury; Proximity effect; In vitro; Lymphocyte; Linear energy transfer; Quantitative analysis; Dose activity relation
• ISSN: 0955-3002; 1362-3095
• DOI: 10.1080/095530098141681

Purpose: To investigate the LET dependence of various yield ratios of intra- and interchromosomal aberrations in order to quantify proximity effects for illegitimate rejoining of chromosome breaks. Materials and methods: Calculations are based on 13 human lymphocyte data sets obtained from in vitro irradiation experiments with various radiation qualities covering an LET range of 0.5 to 150 keV/ mu m. A total of 93 000 first-division metaphases was analysed for all categories of chromosome-type aberrations. Results: No dose dependence was found for the various yield ratios of chromosomal aberrations. No LET dependence became apparent for the yield ratio of inter- to intrachromosomal exchange-type aberrations (dicentrics/centric rings F value). However, a clear LET dependence was found for the yield ratio of intra-arm intrachanges to inter-arm intrachanges (interstitial deletions/centric rings G ratio) and for the yield ratio of intraarm intrachanges to interchromosomal exchanges (interstitial deletions/dicentrics H ratio). Conclusion: Measurements of intrachanges are informative for interpretation and quantification of proximity effects in the formation of radiation-induced chromosome aberrations. In particular, yield ratios for intra-arm intrachanges are likely to have a high potential as an indicator of high-LET radiations.