Abstract
As seen on their family trees, Ile-de-France sheep with scrapie show genetic susceptibility to this disease, which is transmitted via scr s, an autosomal recessive gene. Scrapie occurred in homozygous recessive sheep, whereas the presence of the dominant resistance allele Scr r sufficed to prevent this disease in heterozygous animals. This hypothesis, previously proposed by Parry (1962), was tested in a study involving 133 crossings of sheep of different genotypes, and verified in the observed progenies. In a contaminated environment, susceptibility to the disease seemed to be transmitted by the scr s gene, whose frequency was increasing and varied in different progenies: the gene was propagated by inbreeding combined with selection; scrapie did not appear in the progeny of a homozygous resistant ram with the Scr r/Scrr genotype. On the family trees, linkage between the Scr locus and the OLA-A and -B loci is clearly visible; it often allowed the transmission of resistance or susceptibility haplotypes to be detected by OLA typing and followed from one generation to the next. The Scr r, OLA-A4, B6 haplotype was not found in any diseased sheep born before 1979, but was propagated by healthy sheep. During and after 1979, several recombinations of this haplotype were observed, giving a recombined haplotype with reciprocal linkage (scr s, OLA-A4, B6), disseminated by one sire in particular. The rate of recombination of Scr and OLA loci is estimated to be between 11 and 16 %. The possibility of early selection against the disease without loss of qualities desired by the breeder is discussed.
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Cathala, F., Brown, P., Bouchard, N., Court, L., and Doucet, J.: Maladie de Creutzfeldt-Jakob et Tremblante du mouton. Bull. Acad. Vet. Fr. 52: 99–107, 1979
Chandler, R. L.: Encephalopathy in mice produced with scrapie brain material. Lancet 1: 1378–1379, 1961
Court, L. A.: Virus non conventionnels et affections du système nerveux central. pp. 528, Masson, Paris, 1983
Cuillé, J. and Chelle, P. L.: La maladie dite tremblante du mouton estelle inoculable? C R. Acad. Sci. (Paris) 203: 1552–1554, 1936
Cullen, P. R., Brownlie, J., and Kimberlin, R. H.: Sheep lymphocyte antigens and scrapie. J. Comp. Pathol. 94: 405–415, 1984
Dickinson, A. G. and Meikle, V. M. H.: Host-genotype and agent effects in scrapie incubation: Change in allelic interaction with different strains of agent. Mol. Gen. Genet. 112: 73–79, 1971
Dickinson, A. G., Stamp, J. T., and Renwick, C. C.: Maternal and lateral transmission of scrapie in sheep. J. Comp. Pathol. 84: 19–25, 1974
Fraser, H. and Dickinson, A. G.: Scrapie in mice: Agent strain differences in the distribution and intensity of grey matter vacuolation. J. Comp. Pathol. 83: 29–40, 1973
Gibbs, C. J. and Gajdusek, D. C.: Transmission of scrapie to the cynomolgus monkey (Macaca fascicularis). Nature 236: 73–74, 1972
Joubert, L., Bonneau, M., and Carrier, H.: La tremblante, maladie lente à viroïde. Pathogénie, épidémiologie, prophylaxic. Rev. Med. Vet. 125: 647–666, 1974
Kingsbury, D. T., Kasper, K. C., Stites, D. P., Watson, J. D., Hogan, R. N., and Prusiner, S. B.: Genetic control of scrapie and Creutzfeldt-Jakob disease in mice. J. Immunol. 131: 492–496, 1983
McFarland, D. J., Baker, E. D., and Hotchin, J.: Host and viral genetic determinants of the behavioral effects of scrapie encephalopathy. Physiol. Behav. 24: 911–914, 1980
Millot, P.: Determination d'antigènes lymphocytaires chez les ovins. C. R. Acad. Sci. (D) (Paris) 273: 2028–2030, 1971
Millet, P.: Lymphocyte antigen groups in sheep. Anim. Blood Groups Biochem. Genet. 3: 20–21, 1972
Millot, P.: Genetic control of lymphocyte antigens in sheep: The OLA complex and two minor loci. Immunogenetics 9: 509–534, 1979
Millot, P.: The OLA major histocompatibility complex of sheep. Study of six new factors and evidence of a third locus of the complex OLA-C. Exp. Clin. Immunogenet. 1: 31–42, 1984
Millot, P., Chatelain, J., and Cathala, F.: Le complexe majeur d'histocompatibilité OLA du mouton. Fréquence des facteurs chez des ovins atteints ou non de Tremblante (Scrapie). C. R. Acad. Sci. (III) (Paris) 294: 87–89, 1982
Millot, P., Chatelain, J., and Cathala, F.: Sheep major histocompatibility complex OLA: Gene frequencies in two French breeds with scrapie. Evidence for a linkage between OLA and resistance or susceptibility to the disease. Immunogenetics 21: 117–123, 1985
Parry, H. B.: Scrapie: A transmissible and hereditary disease of sheep. Heredity 17: 75–105, 1962
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Millot, P., Chatelain, J., Dautheville, C. et al. Sheep major histocompatibility (OLA) complex: linkage between a scrapie susceptibility/resistance locus and the OLA complex in Ile-de-France sheep progenies. Immunogenetics 27, 1–11 (1988). https://doi.org/10.1007/BF00404437
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DOI: https://doi.org/10.1007/BF00404437