Abstract
In 1980s, Russell et al. studied the genetic effects of low-dose-rate (LDR) irradiation on male mice using phenotypes such as coat color of mice, however effects at LDR was not observed. Recent advances in genome analysis technology, has enabled more thorough analyses of genomic effects. To clarify incidence of copy number aberrations (CNAs) on the genome of progeny mice, progeny was obtained from C57BL/6J male mice exposed to LDR gamma rays (20 mGy/22 h/day; 0.91 mGy/h) for 400 days (total dose : 8000 mGy) from 8 weeks of age. Using oligo-microarray CGH (Agilent Technologies), we have so far analyzed a total of 107 genomes from mice (32 progenies from six pairs of parents in LDR-irradiated group and 49 progenies from seven pairs of parents in non-irradiated group). In the LDR-irradiated group, four mice had one CNA each, and four other mice had multiple (3~35) CNAs. On the contrary, only five mice from the non-irradiated group had one CNA each. Present results indicate that LDR-irradiated mice had significantly higher frequencies of genomic aberrations than non-irradiated mice (2.09 loci/genome vs 0.10 loci/genome). This study was performed under contract with the Aomori Prefectural Government, Japan.
