Table 1.

Phenotypes of Ptch^DL homozygous mice and negative complementation with the Ptch1^null allele.

Phenotype*	Genotype DL/DL	+/+ and DL/+ and Ptch1-LacZ/+	DL/Ptch1-LacZ
Dead	0	0	17
Exencephaly	0	0	34
Skull vault hypoplasia	100	0	100
Lambdoid suture synostosis	100	0	100#
Narrow basisphenoid	100	0	100
Missing presphenoid	100	0	100
Hypoplastic alisphenoid	100	0	100
Hypoplastic palatal shelves	100	0	100
Coronoid hypoplastic	37.5	0	100
Kinked Tail	0	0	34
Abnormal sternum	100	0	100$
Defective scapulas	12.5	0	50
Affected forelimbs	100	0	100
Affected hindlimbs	100	0	78

^*Numbers represent the percentage of a particular genotype showing an abnormal phenotype for the structure described.

^#Lambdoid suture synostosis was only scored in DL/Ptch1-LacZ embryos that underwent normal neural tube closure and had sufficient development of the calvaria for visualization.

^$Bifurcated and fused ribs occur in association with sternal defects in some embryos.