TABLE 2.
Genotypes of blastocyst-derived colonies cultured with or without MEF feeder layersa
| Type | No. of mice
|
||||
|---|---|---|---|---|---|
| +/+ | +/t | t/t | Unknown | Total | |
| With MEFs | |||||
| Normal ICM colonies | 8 | 15 | 0 | 0 | 23 |
| Aberrant ICM colonies | 0 | 0 | 0 | 9b | 0 |
| Without MEFs | |||||
| Normal ICM colonies | 13 | 26 | 0 | 0 | 39 |
| Aberrant ICM colonies | 0 | 0 | 8 | 3 | 11 |
a
E3.5 embryos produced by mating mice heterozygous for the targeted mutation in the Ssrp1 gene were cultured with and without MEF feeder layers and were genotyped by nested PCR after 4 days.
b
These colonies had degenerated and could not be genotyped.