induction of premature chromosome condensation (pcc) by calyculin a for biodosimetry

background: premature chromosome condensation (pcc) is a method for interphase chromosome analysis in biodosimetry. this study was performed to verify the usefulness of pcc induced by calyculin a in human peripheral blood lymphocytes (pbl) for biological dosimetry and possible construction of dose-response curve. materials and methods: peripheral blood was obtained from a healthy donor and exposed to various doses (0.25–4 gy) of γ -rays. the frequency of simple breaks and dicentrics were scored in g2/m chromosomes of giemsa stained cells. results: results show that the frequency of simple chromosome breaks appears to increase linearly with dose while the frequency of dicentrics apparently increases linear-quadratically with the dose. conclusion: induction of chromosome condensation by calyculin a is a powerful biodisimetric method, which provides a high number of spreads for analysis. with the use of this method, it is possible to overcome problems related to low mitotic index or cell-cycle alterations in routine metaphase analysis and low fusion rate in conventional pcc technique. iran . j. radiat. res., 2004 2 (1): 15-20