Hostname: page-component-77c89778f8-vpsfw Total loading time: 0 Render date: 2024-07-22T12:25:33.683Z Has data issue: false hasContentIssue false

The effect of dose-rate on the yield of translocations and dominant lethals following spermatogonial irradiation of mice

Published online by Cambridge University Press:  14 April 2009

R. J. S. Phillips
Affiliation:
Medical Research Council Radiobiological Research Unit, Harwell, Didcot, Berkshire, England
A. G. Searle
Affiliation:
Medical Research Council Radiobiological Research Unit, Harwell, Didcot, Berkshire, England

Extract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

1. F1 (CSH♀ × 101♂) male mice were given 1200 r. 60Co Υ-irradiation over welve weeks and mated twelve weeks after the end of irradiation. The incidences of foetal and neonatal lethality and of semi-sterility in their offspring were compared with those in controls.

2. Embryonic survival to 15 days in the irradiated series was 98·2% that of controls, while the incidence of semi-sterility was 0·9% compared with nil in the controls. Neither of these differences is significant.

3. Comparison of these results with the significant rates of induction of dominant lethals and translocations in a previous experiment, in which a dose of 1200 r. acute x-irradiation was given to males of the same hybrid stock, show the existence of a dose-rate effect. Its magnitude cannot at present be accurately estimated.

4. The reasons for this effect are discussed. It is concluded that the main cause of the lowered translocation yield is that restitution of breaks will be favoured at low dose-rates, with less opportunity for the formation of interchanges. This could partly account for the lowered rate of induction of dominant lethals as well, but a full explanation is not yet possible.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1964

References

REFERENCES

Carter, T. C. & Lyon, M. F. (1961). An attempt to estimate the induction by X-rays of recessive lethal and visible mutations in mice. Genet. Res. 2, 296305.CrossRefGoogle Scholar
Carter, T. C., Lyon, M. F. & Phillips, R. J. S. (1955). Gene-tagged chromosome translocations in eleven stocks of mice. J. Genet. 53, 154166.CrossRefGoogle Scholar
Lyon, M. F., Phillips, R. J. S. & Searle, A. G. (1964). The overall rates of dominant and recessive lethal and visible mutation induced by spermatogonial x-irradiation of mice. Genet. Res. 5, 448467.CrossRefGoogle Scholar
Neary, G. J., Savage, J. R. K., Evans, H. J. & Whittle, J. (1963). Ultimate maximum values of the RBE of fast neutrons and gamma-rays for chromosome aberrations. Int. J. Rod. Biol. 6, 127136.Google Scholar
Phillips, R. J. S. (1961). A comparison of mutation induced by acute X and chronic gamma irradiation of mice. Brit. J. Radial. 34, 261264.CrossRefGoogle Scholar
Purdom, C. E. & McSheehy, T. W. (1963). Dose-rate and the induction of mutation in Drosophila. Int. J. Rod. Biol. 3, 265275.Google Scholar
Russell, W. L. (1963). The effect of radiation dose rate and fractionation on mutation in mice. Pp. 205218 of Repair from Genetic Radiation Damage, ed. Sobels, . Oxford: Pergamon.Google Scholar
Searle, A. G. (1964). Genetic effects of spermatogonial x-irradiation on productivity of F1 female mice. Mutation Research, 1, 99108.CrossRefGoogle Scholar
Welshons, W. J., Gibson, B. H. & Scandlyn, B. J. (1962). Slide processing for the examination of male mammalian meiotic chromosomes. Stain Tech. 37, 15.CrossRefGoogle ScholarPubMed