... 1998).¹

Abbreviations. DSB = DNA double strand break. Mbp = $10^6$ base pairs. Size = genomic content, measured, e.g., in Mbp. FISH = fluorescent in situ hybridization. CAS = chromosome aberration simulator (Chen et al. 1997, 1998). S&S = a nomenclature system for classifying aberrations (Savage and Simpson 1994, Savage and Tucker 1996).

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... painting²

`One-colour' painting here means that some whole chromosomes are painted with a single FISH colour, the remaining chromosomes are counterstained, and centromeres are recognizable; similarly, `two-colour' painting here refers to whole-chromosome painting with two different fluorochromes and a counterstain; etc.

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....³

Various interpretations of reactive DSBs have been given (Sachs et al. 1997c, 1999). Some approaches (e.g. Chatterjee and Holley 1991, Ballarini et al. 1999) consider them as a biophysically defined subset of all DSBs, which leads to mechanistically calculated values of reactive DSBs per Gy, i.e. this parameter need not be adjusted from the aberration data as in CAS.

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