Table 1.

Genotype of pups and embryos

Parents	Stage	Litter		Pups or embryos
(IS∧GFP/w) (IS∧GFP/w)	3–5 wks	6	(w/w) 12	(IS∧GFP/w) 23	(IS∧GFP/IS∧GFP) 14
(IS∧GFP/w) (GFP/w)	3–5 wks	5	(w/w) 19	(IS∧GFP/w) 18 (GFP/w) 20	(IS∧GFP/GFP) 18
(IS∧GFP/GFP) (IS∧GFP/w)	3–5 wks	3	(IS∧GFP/w) 6	(IS∧GFP/IS∧GFP) 5 (GFP/w) 4	(IS∧GFP/GFP) 6
(GFP/w) (GFP/w)	3 wks	3	(w/w) 6	(GFP/w) 14	(GFP/GFP) 0
	E11.5	4	(w/w) 10	(GFP/w) 24	(GFP/GFP) 0 (16)
	E10.5	5	(w/w) 8	(GFP/w) 16	(GFP/GFP) 9 (2)
	E9.5	4	(w/w) 16	(GFP/w) 22	(GFP/GFP) 18

Genotypes of pups and embryos were determined by PCR. The numbers of dead embryos are indicated in parentheses.