TABLE 1.

Genotypes of progeny from ATX heterozygous intercrosses

Stage	% Genotypea			Total no. of progeny
	+/+	+/−	−/−
E7.5	27	45	27	11
E8.5	20	50	30b	50
E9.5	27	48	25b	103
E10.5	25	60	15c	20
P0	32	68	0	118

^aGenotypes were determined as described in Materials and Methods and Fig. 1 legend.

^bEmbryos were morphologically abnormal, as detailed in Table 2.

^cAll embryos appeared to be necrotic and were partially resorbed.