Analysis of gamma-rays induced chromosome aberrations: a fingerprint evaluation with a combination of pan-centromeric and pan-telomeric probes.
OBJECTIVE
To evaluate the types of induced chromosome aberrations after the exposure of peripheral blood to gamma-rays by the simultaneous detection of all centromeres and telomeres; and to analyse the suitability of different radiation fingerprints for the assessment of radiation quality in cases of recent exposures.


METHODS
Peripheral blood samples were irradiated at 2, 4 and 6 Gy of gamma-rays. Cytogenetic analysis was carried out by fluorescence in situ hybridization (FISH) technique with pan-centromeric and peptide nucleic acid (PNA)-telomeric DNA probes. Cells were analysed using a Cytovision FISH workstation, chromosome aberrations and the length of the acentric fragments were recorded.


RESULTS
The total number of the incomplete chromosome elements was 276. The ratio between incomplete elements and multicentrics was 0.38. The number of acentrics was 1096, 71% were complete acentrics, 15% incomplete acentrics, and 14% interstitial fragments. The relative length of complete, incomplete and interstitial acentrics fragments were 2.70 +/- 0.04, 1.91 +/- 0.07, and 1.42 +/- 0.04 respectively. The mean value of the F-ratio was 11.5 higher than the one, 5.5, previously obtained for alpha-particles. For the G-ratio there was no difference between gamma-rays and alpha-particles, 2.8 and 2.8 respectively. The mean value of the H-ratio for gamma-rays, 0.25, was lower than for alpha-particles 0.40.


CONCLUSIONS
The results support that the percentage of incomplete chromosome aberrations depends on radiation type; low-linear energy transfer (LET) radiation would produces less incomplete aberrations than high-LET radiation. The F- and H-ratios seem to be good indicators of radiation quality, although a real estimation of the H-ratio is only possible using pan-telomeric probes.
Benkhaled
L
L
Unitat d'Antropologia, Dpt. Biologia Animal, Biologia Vegetal i Ecologia, Facultat de Ciències, Universitat Autònoma de Barcelona, Bellaterra, Spain.
Barrios
L
L
Mestres
M
M
Caballin
M R
MR
Ribas
M
M
Barquinero
J F
JF
D000328:Adult; D002503:Centromere / Q000235:genetics / Q000528:radiation effects; D002869:Chromosome Aberrations / Q000528:radiation effects*; D002875:Chromosomes / Q000528:radiation effects*; D016172:DNA Fingerprinting / Q000379:methods*; D015342:DNA Probes / Q000235:genetics*; D004307:Dose-Response Relationship, Radiation; D005720:Gamma Rays; D006801:Humans; D017404:In Situ Hybridization, Fluorescence / Q000379:methods*; D008297:Male; D009000:Monocytes / Q000528:radiation effects*; D011829:Radiation Dosage; D016615:Telomere / Q000235:genetics / Q000528:radiation effects
D015342:DNA Probes