Abstract
We traced the course of radiation induced genomic instability in mouse hemopoietic cells from fetus to adult. Fourteen-day pregnant mice were exposed to 0.5-1Gy 60Co gamma radiation. Chromosomal aberrations were scored in fetal liver cells and postnatal bone marrow up to 18 months of age. Fetal hemopoietic cells and their progeny (CFU-S) showed significantly high number of aberrant metaphases. Such increases were not found in the postnatal bone marrow up to 6 months of age. However, the incidence of metaphases with structural chromosomal aberrations and aneuploidy (hypo- and hyperploidy) increased progressively from 9 to 18 months of age. An interesting finding, not reported earlier, is the progressive increase in chromosome loss with abnormal increase in leukocyte counts. This study demonstrates that a single dose of <1Gy of γ-rays can induce significant genomic instability in the fetal hemopoietic cells, which is transmitted to the postnatal bone marrow and expressed as severe chromosome aneuploidy at advanced ages. This may have a bearing on cancer induction in adult by fetal irradiation. (Supported by the Council of Scientific and Industrial Research, Government of India). [J Radiat Res 44:371 (2003)]
