Mutagenesis vol. 18 no. 6 pp. 539-543,
November 2003
© 2003 UK Environmental Mutagen Society/Oxford University Press
A new cytogenetic approach for the evaluation of mutagenic potential of chemicals that induce cell cycle arrest in the G2 phase
1Health Physics and Environmental Hygiene, National Centre for Scientific Research ‘Demokritos’, Agia Paraskevi, Athens and 2National Institute for Occupational Medicine and Safety, Athens, Greece
The aim of the present study was to develop and standardize a cytogenetic approach for evaluation of the mutagenic potential of chemicals that induce cell cycle arrest in the G2 phase. Even though cytogenetic end-points such as sister chromatid exchange (SCE) have been extensively used to indirectly assess the DNA-damaging potential of various chemicals, they are based on metaphase chromosome analysis. Cells delayed in G2 phase after chemical exposure are not included in conventional SCE analysis. The yield of SCEs obtained, therefore, can be biased, since predominantly undamaged cells proceed to metaphase without delay. To overcome this shortcoming of conventional SCE analysis, the use of a new cytogenetic approach for genotoxic studies is presented that enables the analysis of SCEs directly in G2 phase using drug-induced premature chromosome condensation in cultured peripheral blood lymphocytes. By means of this method, firstly, the possibility that SCE analysis in metaphase chromosomes underestimates the mutagenic potential of various chemicals was tested. Secondly, whether the genotoxic potential of suspected carcinogens could be evaluated using SCE analysis in G2 phase, even at exposures that arrest cells in G2 phase, was examined. Thirdly, whether an important part of the background variation in SCE frequency among individuals is due to the delay of affected cells in G2 phase, rather than to a true biological variation in the cytogenetic end-point used, was tested. The results showed that a higher SCE frequency was scored in G2 phase than in metaphase. Subsequently, the mutagenic potential of chemicals that temporarily arrest cells in G2 phase could now be evaluated more accurately. In addition, it may be of interest to further examine the involvement of cell cycle kinetics in the baseline SCE variation among individuals since a lesser SCE variability was observed when the analysis was carried out in G2 phase rather than at metaphase.
3To whom correspondence should be addressed. Tel: +30 210 6503865; Fax: +30 210 6534710; Email: georgia@ipta.demokritos.gr
CiteULike 
Connotea 
Del.icio.us What's this?
This article has been cited by other articles:
|
|
 |
|
  V. I. Hatzi, G. I. Terzoudi, V. Makropoulos, C. Maravelias, and G. E. Pantelias Pre-irradiation exposure of peripheral blood lymphocytes to glutaraldehyde induces radiosensitization by increasing the initial yield of radiation-induced chromosomal aberrations Mutagenesis, March 1, 2008; 23(2): 101 - 109. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J. E. Swain, J. Ding, D. L. Brautigan, E. Villa-Moruzzi, and G. D. Smith Proper Chromatin Condensation and Maintenance of Histone H3 Phosphorylation During Mouse Oocyte Meiosis Requires Protein Phosphatase Activity Biol Reprod, April 1, 2007; 76(4): 628 - 638. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 G. I. Terzoudi, K. N. Manola, G. E. Pantelias, and G. Iliakis Checkpoint Abrogation in G2 Compromises Repair of Chromosomal Breaks in Ataxia Telangiectasia Cells Cancer Res., December 15, 2005; 65(24): 11292 - 11296. [Abstract] [Full Text] [PDF]
|
|