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Genetic rescue of an endangered mammal by cross-species nuclear transfer using post-mortem somatic cells


Since the advent of procedures for cloning animals, conservation biologists have proposed using this technology to preserve endangered mammals. Here we report the successful cloning of a wild endangered animal, Ovis orientalis musimon, using oocytes collected from a closely related, domesticated species, Ovis aries. We injected enucleated sheep oocytes with granulosa cells collected from two female mouflons found dead in the pasture. Blastocyst-stage cloned embryos transferred into sheep foster mothers established two pregnancies, one of which produced an apparently normal mouflon. Our findings support the use of cloning for the expansion of critically endangered populations.

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Figure 1: Cloned female mouflon with the sheep foster mother.
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  1. Hilton-Taylor, C. (compiler). 2000 IUCN red list of threatened species. (IUCN/SSC; Gland, Switzerland and Cambridge, UK; 2000).

    Google Scholar 

  2. Margules, C.R. & Pressey, R.L. Systematic conservation planning. Nature 405, 243–253 (2000).

    Article  CAS  Google Scholar 

  3. Myers, N., Mittermeier, R.A., Mittermeier, C.G., da Fonseca, G.A.B. & Kent, J. Biodiversity hotspots for conservation priorities. Nature 403, 853–858 (2000).

    Article  CAS  Google Scholar 

  4. Corley-Smith, G.E. & Brandhorst, B.P. Preservation of endangered species and populations: a role for genome banking, somatic cell cloning and androgenesis? Mol. Reprod. Dev. 53, 363–367 (1999).

    Article  CAS  Google Scholar 

  5. Wilmut, I., Schnieke, A.E., McWhir, J., Kind, A.J. & Campbell, K.H.S. Viable offspring derived from fetal and adult mammalian cells Nature 385, 810–813 (1997).

    Article  CAS  Google Scholar 

  6. The cloning debate. Could the thylacine be cloned?

  7. Kenneth, L. Can cloning save endangered species? Curr. Biol. 11, RU 245–246 (2001).

    Article  Google Scholar 

  8. Ryder, O.A., McLaren, A., Brenner, S., Zhang, Y.P. & Benirschke, K. DNA banks for endangered species. Science 288, 275–277 (2000).

    Article  CAS  Google Scholar 

  9. Dominko, T. et al. Bovine oocyte cytoplasm supports development of embryos produced by nuclear transfer of somatic cell nuclei from various mammalian species. Biol. Reprod. 60, 1496–1502 (1999).

    Article  CAS  Google Scholar 

  10. Visscher, P.M., Smith, D., Hall, J.G. & Williams, J.A. A viable herd of genetically uniform cattle. Nature, 409, 303 (2001).

    Article  CAS  Google Scholar 

  11. White, K.L., Bunch, T.D., Mitalipov, S. & Reed, W.A. Establishment of pregnancy after the transfer of nuclear transfer embryos produced from the fusion of argali (Ovis ammon) nuclei into domestic sheep (Ovis aries) enucleated oocytes. Cloning 1, 47–54 (1999).

    Article  CAS  Google Scholar 

  12. Lanza R.P. et al. Cloning of an endangered species (Bos gaurus) using interspecies nuclear transfer. Cloning 2, 79–90 (2000).

    Article  CAS  Google Scholar 

  13. Vogel, G. Cloned Gaur with a short-lived success. Science 291, 409 (2001).

  14. Kato, Y. et al. Eight calves cloned from somatic cells of a single adult. Science 282, 2095–2098 (1998).

    Article  CAS  Google Scholar 

  15. Wakayama, T., Perry, A.C.F., Zuccotti, M., Johnson, K.R. & Yanagimachi, R. Full-term development of mice from enucleated oocytes injected with cumulus cell nuclei. Nature 394, 369–374 (1998).

    Article  CAS  Google Scholar 

  16. Galli, C., Duchi, R., Moor, R.M. & Lazzari, G. Mammalian leukocyte contain all the genetic information necessary for the development of a new individual. Cloning 1, 161–170 (1999).

    Article  CAS  Google Scholar 

  17. Cibelli, J.B. et al. Cloned transgenic calves produced from nonquiescent fetal fibroblasts. Science 280, 1256–1258 (1998).

    Article  CAS  Google Scholar 

  18. Wakayama, T., Rodriguez, I., Perry, A.C.F., Yanagimachi, R. & Monbaerts, P. Mice cloned from embryonic stem cells. Proc. Natl. Acad. Sci. USA 96, 14984–14989 (1999).

    Article  CAS  Google Scholar 

  19. Kikyo, N. & Wolffe, A.P. Reprogramming nuclei: insights from cloning, nuclear transfer and heterokaryons. J. Cell. Sci. 113, 11–20 (2000).

    CAS  PubMed  Google Scholar 

  20. Kikyo, N., Wade, P.A., Guschin, D., Ge, H. & Wolffe, A.P. Active remodeling of somatic nuclei in egg cytoplasm by the nucleosomal ATPase ISWI. Science 289, 2360–2362 (2000).

    Article  CAS  Google Scholar 

  21. Steinborg, R. et al. Mitochondrial DNA heteroplasmy in cloned cattle produced by fetal and adult cell cloning. Nat. Genet. 25, 255–257 (2000).

    Article  Google Scholar 

  22. Evans, M.J. et al. Mitochondrial DNA genotypes in nuclear transfer-derived cloned sheep. Nat. Genet. 23, 90–93 (1999).

    Article  CAS  Google Scholar 

  23. Ptak, G., Loi, P., Dattena, M., Tischner, M. & Cappai, P. Offspring from one-month old lambs: studies on the developmental capability of prepubertal oocytes. Biol. Reprod. 61, 1568–1574 (1999).

    CAS  Google Scholar 

  24. Loi, P., Ledda, S., Fulka, J. Jr., Cappai, P. & Moor, R.M. Development of parthenogenetic and cloned embryos: effect of activation protocols. Biol. Reprod. 58, 1177–1187 (1998).

    Article  CAS  Google Scholar 

  25. Campbell, K.H.S., Loi, P., Otaegui, P.J. & Wilmut, I. Cell cycle co-ordination in embryo cloning by nuclear transfer. Rev. Reprod. 1, 40–46 (1996).

    Article  CAS  Google Scholar 

  26. Jamieson, A. The effectiveness of using co-dominant polymorphic allelic series for (1) checking pedigrees and (2) distinguish full-sib pair members. Anim. Genet. (Suppl.) 1, 37–44 (1994).

    Article  Google Scholar 

  27. Hanset, R. Probalité d'exclusion de paternité et de monozygotie, probabilité de similitude, generalization a N alleles co-dominants. Ann. Med. Vet. 119, 71–80 (1974).

    Google Scholar 

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Special thanks go to Dr. Cesare Galli (Laboratorio di Tecnologie della Riproduzione, Cremona, Italy) for constructive discussions throughout the experiments. The authors also acknowledge Dr. Michele Blasi for the microsatellite analysis, Dr. Maria Dattena and Mr. Fabrizio Chessa for help with surgery, and Mr. Giampiero Camoglio and Mr. Antonio Pintadu for animal care. J.F. is supported by GACR 524/96/K162.

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Correspondence to Pasqualino Loi.

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Loi, P., Ptak, G., Barboni, B. et al. Genetic rescue of an endangered mammal by cross-species nuclear transfer using post-mortem somatic cells. Nat Biotechnol 19, 962–964 (2001).

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