Table 1.
Influence of the genetic background on the time of GRIP1−/− embryonic lethality
| Age | (129/J × ICR) F1
|
Age | (129/J × ICR) F3
|
||||
|---|---|---|---|---|---|---|---|
| +/+ | +/− | −/− | +/+ | +/− | −/− | ||
| E 3.5 | 13 | 24 | 11 | E 12 | 66 | 121 | 35 |
| E 7.5 | 23 | 51 | 0 | E 14 | 71 | 153 | 31 |
| P 30 | 108 | 203 | 0 | E 16 | 28 | 67 | 4 |
| P 30 | 64 | 110 | 0 | ||||
The frequencies of +/+, +/− and −/− GRIP1 mutants were compared in the progenies of (129/J × ICR)F1 and F3 intercrosses. Approximate Mendelian frequencies of GRIP1 mutants were obtained at E3.5 and E12 in the progeny of F1 and F3 intercrosses, respectively. The viability of GRIP1−/− embryos was significantly prolonged by backcrossing into the ICR background.