Chromosomal instability in haemopoietic cells of the foetus, mother and offspring after in utero irradiation of the CBA/Ca mouse.
OBJECTIVE
The present study was conducted to test the susceptibility of the mouse foetus to transmit chromosomal instability to the haemopoietic stem cells of offspring after in utero X-or plutonium-239-irradiation.


METHODS
Pregnant CBA/Ca-mice were injected with 80 kBq/kg 239Pu or X-irradiated with 1 Gy X-rays on days 13 or 14 of gestation. CFU-A cultures were grown from haemopoietic stem cells sampled from foetal liver and the bone marrow from the offspring and from the mother. Non-clonal, unstable chromosomal aberrations were scored in metaphases from individual stem cell colonies.


RESULTS
The relative excess (RE) of unstable chromosomal aberrations in foetal liver cells irradiated with 1 Gy X-rays increased from 1.6 at day 2 up to 2.7 at day 4 after irradiation. In the bone marrow cells from the mother, this value was 1.8 (average from cells sampled at days 3 and 14 after irradiation). After injection of the pregnant mice with 235Pu, the yield of unstable chromosomal aberrations per cell was 0.14+/-0.03 (RE approximately 10) in descendants of bone marrow cells from the mother, 0.11+/-0.02 (RE = 10) in descendants of foetal liver cells and 0.16+/-0.05 (RE = 10) in descendants of bone marrow cells from the offspring.


CONCLUSIONS
From the numerical analysis of non-clonal, unstable aberrations in haemopoietic cells from the foetus, the mother and the offspring after in utero irradiation, it was concluded that in utero irradiation of the CBA/Ca mouse was not more efficient in inducing chromosomal instability in the offspring than in the foetus or the mother. All three cell populations exhibited a similar degree of unstable aberrations, both in terms of the absolute numbers of non-clonal aberrations and in terms of relative excess compared with unexposed controls.
Rosemann
M
M
Institute of Pathology, GSF Forschungszentrum für Umwelt und Gesundheit, Neuherberg, Germany. rosemann@gsf.de
Milner
A
A
Lambert
B E
BE
D000818:Animals; D001854:Bone Marrow Cells / Q000528:radiation effects / Q000648:ultrastructure; D002869:Chromosome Aberrations; D005260:Female; D005333:Fetus / Q000528:radiation effects*; D006412:Hematopoietic Stem Cells / Q000528:radiation effects* / Q000648:ultrastructure; D051379:Mice; D008808:Mice, Inbred CBA; D011005:Plutonium; D011247:Pregnancy; D014965:X-Rays
D011005:Plutonium