Chromosomal intrachanges induced by swift iron ions.
We measured the induction of structural aberrations in human chromosome 5 induced by iron ions using the novel technique of multicolor banding in situ hybridization (mBAND). Human lymphocytes isolated from whole blood were exposed in vitro to 500 MeV/n (LET=200 keV/micrometers, doses 1 or 4 Gy) Fe nuclei at the HIMAC accelerator in Chiba (Japan). Chromosomes were prematurely condensed by calyculin A after 48 h in culture and slides were painted by mBAND. We found a frequency of 0.11 and 0.57 residual breakpoints per chromosome 5 after 1 and 4 Gy Fe-ions, respectively. Inter-chromosomal exchanges were the prevalent aberration type measured at both doses, followed by terminal deletions, and by intra-chromosomal exchanges. Among intra-chromosomal exchanges, intra-arm events were more frequent than inter-arm, but a significant number of intra-changes was associated to inter-changes involving the same chromosome after 4 Gy of iron ions. These events show that the complexity of chromosomal exchanges induced by heavy ions can be higher than expected by previous FISH studies.
Hortsmann
M
M
Department of Genetics, University of Duisburg-Essen, Essen, Germany.
Durante
M
M
Johannes
C
C
Obe
G
G
D002869:Chromosome Aberrations; D019457:Chromosome Breakage / Q000235:genetics; D002905:Chromosomes, Human, 4-5 / Q000528:radiation effects; D004307:Dose-Response Relationship, Radiation; D020450:Heavy Ions; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D007501:Iron; D008214:Lymphocytes / Q000528:radiation effects*; D010315:Particle Accelerators
D007501:Iron