Abstract
As a standard biodosimeter, scoring chromosomal aberrations is widely used (cytogenetic biodosimeter). However, when cells are irradiated with large doses (more than 10 Gy), most cells arrest in G2 phase and do not enter mitosis and it is thus difficult or even impossible to obtain chromosomes using conventional colcemid block. Therefore, this problem has limited the use of cytogenetic biodosimeter for estimate the irradiation dose over 10 Gy. Recently, Gotoh and Asakawa first overcame this limitation using their developed drug induced premature chromosome condensation (PCC) method. Based on this report, Kanda et al. then proposed an easy method for biodosimeter by scoring Giemsa stained ring chromosomes using drug induced PCC method. Here we report that the total number of Giemsa stained prematurely condensed chromosomes well correlates to the irradiation dose, and combined with the PCC index, it is possible to estimate the irradiation dose up to 40 Gy with quite ease and quick. Therefore, we propose this simple protocol for a new cytogenetic biodosimeter. [J Radiat Res 44:431 (2003)]
