Table 1.
Efficiency of OTOF mutant lambs generation induced by CRISPR-Cas9 system using either Cas9 mRNA or Cas9 protein (RNP).
| Overall results | Cas9 mRNA vs. Cas9 RNP | |||||
|---|---|---|---|---|---|---|
| mRNA 50 ng/µl | RNP 100 ng/µl | RNP 250 ng/µl | RNP 500 ng/µl | P value | ||
| Number of recipient females | 247 | 103 | 48 | 49 | 47 | — |
| Number of transferred embryos | 1,316 | 629 | 218 | 236 | 233 | — |
| Pregnant/transferred recipients |
25.1% (62/247) |
16.5%a (17/103) |
45.8%b (22/48) |
24.5%a (12/49) |
23.4%a(11/47) | <0.05 |
| Embryos alive at 30 d of gestation | 78 | 19 | 33 | 14 | 12 | — |
| Fetal losses (from 30 d of gestation to birth) |
6.4% (5/78) |
5.3% (1/19) |
6.1% (2/33) |
7.1% (1/14) |
8.3% (1/12) |
NS |
| Lambs born | 73 | 18 | 31 | 13 | 11 | — |
| Lamb survival rate* |
89.0% (65/73) |
77.8% (14/18) |
93.5% (29/31) |
100% (13/13) |
81.8% (9/11) |
NS |
| Mutants/lambs born |
17.8% (13/73) |
27.8%a (5/18) |
6.5%b (2/31) |
7.7%b (1/13) |
45.5%a (5/11) |
<0.05 |
| KI/mutant lambs |
61.5% (8/13) |
60.0% (3/5) |
50.0% (1/2) |
100% (1/1) |
60.0% (3**/5) |
NS |
| KI/total lambs |
11.0% (8/73) |
16.7% (3/18) |
3.2% (1/31) |
7.7% (1/13) |
2.7% (3**/11) |
NS |
For superscripts a vs. b, p < 0.05.
*Lambs alive at first week after birth.
**Out of three lambs, two are mosaic.