. 2001 Jan 1;21(1):169–175. doi: 10.1523/JNEUROSCI.21-01-00169.2001

Table 1.

Genotypes of embryos and live-born mice generated from interbreeding ofbcl-x^+/−/caspase-9^+/− mice

Genotypes (expected frequency, %)	Number of E12.5 mice (%)	Number of live-born mice (%)
bcl-x^+/+/casp9^+/+(6.25)	6 (4.3)	22 (31.9)
bcl-x^+/+/casp9^+/−(12.5)	21 (14.8)	22 (31.9)
bcl-x^+/+/casp9^−/−(6.25)	10 (7.1)	3 (4.3)
bcl-x^+/−/casp9^+/+(12.5)	14 (9.9)	9 (13.0)
bcl-x^+/−/casp9^+/−(25.0)	31 (22.0)	25 (36.2)
bcl-x^+/−/casp9^−/−(12.5)	24 (17.0)	0 (0)
bcl-x^−/−/casp9^+/+(6.25)	20 (14.2)	0 (0)
bcl-x^−/−/casp9^+/−(12.5)	9 (6.4)	0 (0)
bcl-x^−/−/casp9^−/−(6.25)	6 (4.3)	0 (0)

Nine different genotypic combinations resulted from the interbreeding ofbcl-x^+/−/caspase-9^+/− mice, shown in column 1. A total of 141 E12.5 embryos were generated in 23 litters. All nine genotypes were found and followed the predicted Mendelian distribution. Sixty-nine live-born mice were generated in 15 litters. No bcl-x^−/− were born, indicating that these mice were embryonic lethal. Live-borncaspase-9^−/− mice were also rare, consistent with perinatal lethality.