Irradiation at Different Fetal Stages Results in Different Translocation Frequencies in Adult Mouse Thyroid Cells.

Irradiation at Different Fetal Stages Results in Different Translocation Frequencies in Adult Mouse Thyroid Cells. Radiat Res. 2016 Sep 14; Authors: Hamasaki K, Landes RD, Noda A, Nakamura N, Kodama Y Abstract While it is generally believed that fetuses are at high risk of developing cancers, including leukemia, after low doses of radiation, it has been reported that atomic bomb survivors exposed in utero did not show a dose response for translocations in blood T lymphocytes when they were examined at approximately 40 years of age. Subsequent mouse studies confirmed that animals irradiated during the fetal stage did not show evidence of radiation effects in lymphocytes and bone marrow cells when they were examined after reaching adulthood. However, in a study of rat mammary epithelial cells, radiation effects were clearly observed after fetal irradiation. These results indicate that the fate of chromosome aberrations induced in a fetus could vary among different tissues. Here we report on translocation frequencies in mouse thyroid cells, which were irradiated at different stages of fetal development before undergoing cytogenetic examination using fluorescence in situ hybridization (FISH) painting of chromosomes 1 and 3. Adult mice, 2 Gy X-ray irradiated at 15.5-day-old fetuses (E15.5), showed a higher translocation frequency (30/1,155 or 25.3 × 10(-3)) than nonirradiated adult controls (0/1,007 or 0.1 × 10(-3)), and was near that e...
Source: Radiation Research - Category: Physics Authors: Tags: Radiat Res Source Type: research