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Digynic triploidy in rabbit blastocysts after delayed insemination

Published online by Cambridge University Press:  14 April 2009

R. A. Beatty
Affiliation:
A.R.C. Unit of Animal Genetics, Department of Genetics, University of Edinburgh, West Mains Road, Edinburgh EH9 3JN
V. J. Coulter
Affiliation:
A.R.C. Unit of Animal Genetics, Department of Genetics, University of Edinburgh, West Mains Road, Edinburgh EH9 3JN
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The origin of triploid (3N) 5½-day blastocysts in rabbits is inferred from the segregation of sex chromosomes and of an autosomal M-marker whose properties are described. 39 triploids and no tetraploids were scored among 1454 chromosomally scored blastocysts. A delay of 8 h between an ovulatory injection and subsequent insemination raised the estimated normal incidence of 0·59% triploid blastocysts to 3·13%. The increase is ascribed primarily to digyny (17 blastocysts), and to diandry probably mediated by dispermy (1 blastocyst). The triploid components of the two 2N/3N mosaics and the one 3N/6N were digynic. Neither superovulation nor insemination of excessive numbers of spermatozoa could be shown to give rise to triploid embryos. The diandric triploid was X Y Y, the first of this constitution apparently reported in the rabbit. There was some evidence that X X Y triploid blastocysts up to 5½-day gestation are more viable than X X X. In the 2N/3N mosaics each component had been entered by one spermatozoon, and the dliploid component could not have been merely a contamination by dliploid maternal somatic cells. In 2N/4N, 2N/4N/8N and 3N/6N mosaics, each polyploid component showed an exact doubling of the marker chromosome constitution of a component of lower ploidy; their origin is ascribed to doubling or redoubling of chromosome number in isolated embryonic cells. With earlier data included, 49·08 (± s.e. 1·96)% of 652 diploid blastocysts were X Y. 460 non-experimental weaned rabbits were all cliploid.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1978

References

REFERENCES

Beatty, R. A. (1978). The origin of human triploidy: an integration of qualitative and quantitative evidence. Annals of Human Genetics 41, 299314.CrossRefGoogle ScholarPubMed
Beatty, R. A., Lim, M.-C. & Coulter, V. J. (1975). A quantitative study of the second meiotic metaphase in male mice (Mus musculus). Cytogenetics and Cell Genetics 15, 256275.CrossRefGoogle ScholarPubMed
Centerwall, W. R. & Benirschke, K. (1973). Male tortoiseshell and calico (T-C) cats. Journal of Heredity 64, 272278.CrossRefGoogle ScholarPubMed
Dewald, G., Alvarez, M. N., Cloutier, M. D., Kelalis, P. P. & Gordon, H. (1975). A diploid-triploid human mosaic with cytogenetic evidence of double fertilization. Clinical Genetics 8, 149160.CrossRefGoogle ScholarPubMed
Evans, E. P., Breckon, G. & Ford, C. E. (1964). An air-drying method for meiotic preparations from mammalian testes. Cytogenetics 3, 289294.CrossRefGoogle ScholarPubMed
Fechheimer, N. S. & Beatty, R. A. (1974). Chromosomal abnormalities and sex ratio in rabbit blastocysts. Journal of Reproduction and Fertility 37, 331341.CrossRefGoogle ScholarPubMed
Fechheimer, N. S. & Jaap, R. G. (1978). The parental source of heteroploidy in chick embryos determined with chromosomally marked gametes. Journal of Reproduction and Fertility 52, 141146.CrossRefGoogle ScholarPubMed
Fujimoto, S., Pahlavan, N. & Dukelow, W. R. (1974). Chromosome abnormalities in rabbit preimplantation blastocysts induced by superovulation. Journal of Reproduction and Fertility 40, 177181.CrossRefGoogle ScholarPubMed
Hofsaess, F. R. & Meacham, T. N. (1971). Chromosome abnormalities of early rabbit embryos. Journal of Experimental Zoology 177, 912.CrossRefGoogle ScholarPubMed
Issa, M., Atherton, G. W. & Blank, C. E. (1968). The chromosomes of the domestic rabbit Oryctolagus cuniculus. Cytogenetics 7, 361375.CrossRefGoogle ScholarPubMed
Martin-Deleon, P. A. (1972). Morphologically distinctive X chromosome in the female chromosome complement of the rabbit. Canadian Journal of Genetics and Cytology 14, 817821.CrossRefGoogle Scholar
Martin, P. A. & Shaver, E. L. (1972). Sperm aging in utero and chromosomal anomalies in rabbit blastocysts. Developmental Biology 28, 480486.CrossRefGoogle ScholarPubMed
Miller, R. C. (1971). Chromosome abnormalities in 16 to 18 hour chick embryos: a study of incidence and modes of origin. Ph.D. Dissertation, The Ohio State University.Google Scholar
Mortimer, D. (1977). The survival and transport to the site of fertilization of diploid rabbit spermatozoa. Journal of Reproduction and Fertility 51, 99104.CrossRefGoogle Scholar
Niebuhr, E. (1974). Triploidy in man. Cytogenetical and clinical aspects. Humangenetik 21, 103125.Google ScholarPubMed
Rieck, G. W. (1973). Numerical aberrations of gonosomes and reproductive failure in cattle. In Les Accidents Chromosomiques de la Reproduction (ed. Boué, A. and Thibault, C.), pp. 165187. Paris: INSERM.Google Scholar
Schindler, A. M. & Mikamo, K. (1970). Triploidy in man. Report of a case and a discussion on aetiology. Cytogenetics 9, 116130.CrossRefGoogle Scholar
Shaver, E. L. (1970). The chromosome complement of blastocysts from rabbits injected with various doses of HCG before ovulation. Journal of Reproduction and Fertility 23, 335337.CrossRefGoogle ScholarPubMed
Shaver, E. L. & Carr, D. H. (1967). Chromosome abnormalities in rabbit blastocysts following delayed fertilization. Journal of Reproduction and Fertility 14, 415420.CrossRefGoogle ScholarPubMed
Shaver, E. L. & Carr, D. H. (1969). The chromosome complement of rabbit blastocysts in relation to the time of mating and ovulation. Canadian Journal of Genetics and Cytology 11, 287293.CrossRefGoogle Scholar
Takagi, N. & Sasaki, M. (1976). Digynic triploidy after superovulation in mice. Nature 264, 278281.CrossRefGoogle ScholarPubMed
Widmeyer, M. A. & Shaver, E. L. (1972). Estrogen, progesterone and chromosome abnormalities in rabbit blastocysts. Teratology 6, 207214.CrossRefGoogle ScholarPubMed