Although the National Institute of Health (NIH, USA) miniature pigs were developed specifically for xenotransplantation, the cloning efficiency is still very low. To increase the efficiency, an advanced somatic cell nuclear transfer (SCNT) method may need. In the present study, we report the productions of genetically modified cloned pigs using the frozen-thawed donor cells without culture before SCNT. Fibroblasts were isolated from an ear skin of a 10-day-old NIH miniature pig. The fibroblast cells were genetically modified with the human CD73 (hCD73). For SCNT, somatic cells transfected with hCD73 were used as donor cells. The survival rate of the somatic cells was significantly higher in 0 h (95%) compared with 1 h (81%) after thawing (p<0.05). We obtained the pregnancy (38.9%, 7/18) and delivery (11.1%, 2/18) rate, respectively. Totally 7 genetically modified cloned piglets were delivered. Among them, 2 piglets were survived and 5 piglets were born stillbirth. The healthy 2 piglets are still survived (≥6 months).

• Dae-Jin Kwon(Animal Biotechnology Division, National Institute of Animal Science, RDA)
• Seongsoo Hwang(Animal Biotechnology Division, National Institute of Animal Science, RDA)
• Keon Bong Oh(Animal Biotechnology Division, National Institute of Animal Science, RDA)
• Tae-Uk Kwak(Animal Biotechnology Division, National Institute of Animal Science, RDA)
• Dong-Hoon Kim(Animal Biotechnology Division, National Institute of Animal Science, RDA)
• Jae-Seok Woo(Animal Biotechnology Division, National Institute of Animal Science, RDA)
• Jin-Ki Park(Animal Biotechnology Division, National Institute of Animal Science, RDA)
• Gi-Sun Im(Animal Biotechnology Division, National Institute of Animal Science, RDA)