A highly efficient method for porcine cloning by nuclear transfer using in vitro-matured oocytes. Academic Article uri icon


  • To date, the efficiency of pig cloning by nuclear transfer of somatic cell nuclei has been extremely low, with less than 1% of transferred embryos surviving to term. Even the utilization of complex procedures such as two rounds of nuclear transfer has not resulted in greater overall efficiencies. As a result, the applicability of the technology for the generation of transgenic and cloned animals has not moved forward rapidly. We report here a simple nuclear transfer protocol, utilizing commercially available in vitro-matured oocytes, that results in greater than 5% overall cloning efficiency. Of five recipients receiving nuclear transfer embryos produced with a fetal fibroblast cell line as nuclear donor, all five established pregnancies by day 28 (100%), and 4/5 (80%) went to term. Efficiencies for each transfer were 7% (9 piglets/128 doublets transferred), 5% (5/100), 12% (7/59), and 6.6% (7/106). The overall efficiency in all recipients was 5.5% and in pregnant recipients 7.7%, with a total of 28 cloned piglets produced. With the average fusion rate being 58%, the percentage of fused doublets producing a live piglet approached 12%. The method described here can be undertaken by a single micromanipulator at a reasonable cost, and should facilitate the broad utilization of porcine cloning technology in transgenic and nontransgenic applications.

published proceedings

  • Cloning Stem Cells

altmetric score

  • 6

author list (cited authors)

  • Walker, S. C., Shin, T., Zaunbrecher, G. M., Romano, J. E., Johnson, G. A., Bazer, F. W., & Piedrahita, J. A.

citation count

  • 122

complete list of authors

  • Walker, Shawn C||Shin, Taeyoung||Zaunbrecher, Gretchen M||Romano, Juan E||Johnson, Greg A||Bazer, Fuller W||Piedrahita, Jorge A

publication date

  • January 2002