title: Chromosome instability of HPRT-mutant subclones induced by ionising radiation of various LET.
abstract: The induction of HPRT-mutations and survival of Chinese hamster cells (line B11ii-FAF28, clone 431) were studied after irradiation by 4He and 12C-ions of various LET (20-360 keV/micrometers), produced by the U-200 heavy ion accelerator. The RBE increases with LET up to the maximum at 100-200 keV/micrometers and then decreases. Cytogenetic analysis was performed on the HPRT-mutant subclones selected from unirradiated Chinese hamster V-79 cells and from HPRT-mutant subclones that arose after exposure to gamma-rays, 1 GeV protons and 14N-ions (LET-77 keV/micrometers), produced by the synchrophasotron and the U-400M heavy ion accelerator. Slow growing mutant subclones were observed. The cytogenetic properties of individual clones were highly heterogeneous and chromosome instability was observed in both spontaneous and radiation-induced mutants. Chromosome instability was highest among spontaneous mutants and decreased with increasing LET.
authors.affiliation: Joint Institute for Nuclear Research (JINR), Division of Radiation and Radiobiological Research (DRRR), Dubna, Moscow region, Russia.
authors.forename: R D
authors.initials: RD
authors.lastname: Govorun
authors.forename: I V
authors.initials: IV
authors.lastname: Koshlan
authors.forename: N A
authors.initials: NA
authors.lastname: Koshlan
authors.forename: E A
authors.initials: EA
authors.lastname: Krasavin
authors.forename: N L
authors.initials: NL
authors.lastname: Shmakova
mesh_terms: D000818:Animals; D002244:Carbon; D002460:Cell Line; D002468:Cell Physiological Phenomena / Q000528:radiation effects; D002470:Cell Survival / Q000528:radiation effects; D002869:Chromosome Aberrations; D006224:Cricetinae; D003412:Cricetulus; D004307:Dose-Response Relationship, Radiation; D020450:Heavy Ions; D006371:Helium; D007041:Hypoxanthine Phosphoribosyltransferase / Q000235:genetics*; D018499:Linear Energy Transfer; D009154:Mutation; D010315:Particle Accelerators; D012062:Relative Biological Effectiveness
chemical_list: D006371:Helium; D002244:Carbon; D007041:Hypoxanthine Phosphoribosyltransferase