Incomplete chromosome exchanges are not fingerprints of high LET neutrons.

MGC, Department of Radiation Genetics and Chemical Mutagenesis, Leiden University Medical Centre, Wassenaarseweg 72, 2333AL, Leiden, The Netherlands.
Radiation Protection Dosimetry (Impact Factor: 0.91). 02/2002; 99(1-4):215-6.
Source: PubMed

ABSTRACT A new fluorescence in situ hybridisation (FISH) technique combining whole chromosome specific DNA libraries with pan-centromeric DNA and telomeric PNA probes was introduced to investigate the induction of chromosome exchanges in human lymphocytes after exposure to low (4 Gy X rays) and high (1 Gy neutrons) linear energy transfer radiation. This combination of probes allowed accurate detection of exchange aberrations involving the painted chromosomes and an unambiguous discrimination between complete and incomplete exchanges, as well as terminal and interstitial deletions. Data obtained in the present study using combined FISH assay with telomeres detection showed no differences between two types of radiation regarding the induction of incomplete exchanges.

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