title: Non-proportional involvement of Chinese hamster chromosomes 3, 4, 8 and 9 in X-ray-induced chromosomal aberrations.
abstract: OBJECTIVE
  To study by fluorescence in situ hybridization (FISH) the involvement of Chinese hamster chromosomes 3, 4, 8, and 9, and their separate chromosome arms in X-ray-induced aberrations.
  
  
  METHODS
  Male embryonic primary cells of Chinese hamster were used and metaphases were collected and scored at 20 h after confluent cells were exposed to 1 and 4 Gy X-rays. The frequencies and types of chromosomal aberrations involving chromosomes 3, 4, 8, and 9 were studied by FISH using arm-specific painting probes. Proportional distribution of the induced aberrations was tested on the basis of the relative lengths of chromosomes or chromosome arms studied.
  
  
  RESULTS
  A non-proportional distribution of breaks, colour junctions as well as apparently simple dicentrics and translocations among the chromosomes studied was observed in the 4 Gy group. In general, chromosome 3 was less involved than expected and chromosome 8 was more involved than expected, and chromosomes 4 and 9 were involved as expected. A non-proportional involvement of arms in breaks, colour junctions and apparently simple dicentrics was also observed. The short arm of chromosome 3 was more involved in breaks and colour junctions than expected. The long arm of chromosome 4 was more involved in dicentrics than expected.
  
  
  CONCLUSIONS
  Results of this study indicate a non-proportional involvement of Chinese hamster chromosomes 3, 4, 8 and 9 as well as their arms in different types of aberrations following irradiation.
authors.affiliation: Department of Radiation Genetics and Chemical Mutagenesis, Leiden University Medical Centre, The Netherlands.
authors.forename: Y
authors.initials: Y
authors.lastname: Xiao
authors.forename: A T
authors.initials: AT
authors.lastname: Natarajan
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D002869:Chromosome Aberrations; D002873:Chromosome Fragility; D002875:Chromosomes / Q000528:radiation effects*; D006224:Cricetinae; D003412:Cricetulus; D004249:DNA Damage; D015342:DNA Probes; D004622:Embryo, Mammalian; D017404:In Situ Hybridization, Fluorescence; D008297:Male; D011829:Radiation Dosage
chemical_list: D015342:DNA Probes