title: Chromosome fragmentation after irradiation with C ions.
abstract: The premature chromosome condensation (PCC) technique has been used to compare chromatin breakage and repair in non-cycling CHO-K1 cells following high LET (C ions) and low LET (X-rays) irradiation. For both radiation qualities the average initial number of excess PCC fragments increases linearly with dose. However, the frequency of chromatin breaks follows the pattern of energy deposition and at higher LET values reveals clustering due to the large number of ionizing events being concentrated in a small volume of the cell nucleus. In consequence, the distribution of PCC chromosomes plus excess fragments among cells has followed Poisson statistics after X-ray irradiation while the overdispersion of the frequencies has been observed after C-irradiation indicating that a single particle traversal through a cell nucleus can produce multiple chromatin lesions.
authors.affiliation: M. Smoluchowski Institute of Physics, Jagellonian University, Reymonta 4, 30059 Kraków, Poland. gudowska@th.if.uj.edu.pl
authors.forename: Ewa
authors.initials: E
authors.lastname: Gudowska-Nowak
authors.forename: Elena
authors.initials: E
authors.lastname: Nasonova
authors.forename: Sylvia
authors.initials: S
authors.lastname: Ritter
authors.forename: Michael
authors.initials: M
authors.lastname: Scholz
mesh_terms: D000818:Animals; D016466:CHO Cells; D002244:Carbon; D002869:Chromosome Aberrations; D006224:Cricetinae; D004260:DNA Repair; D020450:Heavy Ions; D018499:Linear Energy Transfer; D016012:Poisson Distribution
chemical_list: D002244:Carbon