Table 3.
Timing of nuclear reprogramming events following SCNT
| Hours after activation | Interphase | PCC a | PN b |
|---|---|---|---|
| 2 | 23.8% (5/21) | 71.4% (15/21) | 4.8% (1/21) |
| 4 | 5.9% (2/34) | 41.2% (14/34) | 52.9% (18/34) |
| 6 | 3.7% (1/27) | 11.1% (3/27) | 85.2% (23/27) |
In these studies, we evaluated reconstruction of 174 embryos of which 82 were stained to evaluate PCC formation and 92 were cultured in vitro to evaluate embryogenesis. In these studies, 80% progressed to cleavage, 35% progressed to morula, and 16% progressed to blastocysts. The percentage in each category found at the given time points is shown with the fraction of reconstructed embryos analyzed in parentheses. A total of 16 Jills were used for these experiments, and oocytes were collected in the absence of hormonal stimulation by mating with vasectomized males.
a
PCC: premature chromosome condensation.
b
PN: pronuclei. Results are shown following fibroblast cell fusion and activation.