The analysis of stable radiation-induced translocations in mice using chromosome painting

Journal Article · Wed Nov 01 04:00:00 EST 1995 · Environmental and Molecular Mutagenesis

OSTI ID:115149

Spruill, M D; Nath, J ^[1]; Ramsey, M J ^[2]

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1. West Virginia Univ., Morgantown, WV (United States)
2. Lawrence Livermore National Lab., CA (United States); and others

The mouse is an excellent model for estimating human risk from adverse environmental exposure. However, the mouse karyotype consists entirely of acrocentric chromosomes that are very similarly sized, making studies involving stable cytogenetic damage difficult or impossible to perform. Chromosome-specific composite DNA probes for the mouse have allowed the use of fluorescence in situ hybridization, or chromosome painting, to detect even subtle translocations quickly and easily. To assess the stability of radiation-induced translocations, C57BL/6 mice were given a whole body acute dose of 0, 1, 2, 3 or 4 Gy {sup 137}Cs gamma rays at 8 weeks of age. Peripheral blood and bone marrow were taken from four mice in each dose group at 1, 8, 15 and 30 days post-irradiation. Probes specific for chromosomes 2 and 8 were used. The equivalent of 100 cells from each tissue was scored for each mouse. DAPI counterstain was used for centromere detection because it brightly stains the centromeric heterochromatin; however, two types of rearrangements involving this region have shown that it is not always a true marker for the functional centromere. Results have shown that the percentage of reciprocal translocations remained constant in both tissues. In contrast, the frequency of non-reciprocal translocations, which remained constant in the peripheral blood, decreased after a week in bone marrow, but then remained constant out to 30 days. Dicentrics decreased in both tissues, with almost none remaining in the bone marrow after 8 days. These data suggest that translocations will persist throughout the animal`s life span and be an adequate biodosimeter for radiation exposure.

• DOE Contract Number: W-7405-ENG-48
• OSTI ID: 115149
• Report Number(s): CONF-9503160--
• Journal Information: Environmental and Molecular Mutagenesis, Journal Name: Environmental and Molecular Mutagenesis Journal Issue: Suppl.25 Vol. 25; ISSN 0893-6692; ISSN EMMUEG
• Country of Publication: United States
• Language: English

Related Subjects

56 BIOLOGY AND MEDICINE
APPLIED STUDIES
BIOLOGICAL INDICATORS
CHROMOSOMAL ABERRATIONS
GENETIC RADIATION EFFECTS
MICE
RADIATION DOSES
STABILITY