Table 2.

Distribution and Frequency of Axial Skeletal Defects

	Cervical	Thoracic	Rib	Lumbar	Sacral	Caudal
(C57Bl/6J X 129S1/SvImJ)F2
−/−	0% (0/12)	25% (3/12)	33% (4/12)	17% (2/12)	17% (2/12)	17% (2/12)
littermates	0% (0/14)	7% (1/14)	0% (0/14)	0% (0/14)	0% (0/14)	0% (0/14)
129S1/SvImJ
−/−	0% (0/8)	100% (8/8)	100% (8/8)	87% (7/8)	50% (4/8)	37% (3/8)
littermates	0% (0/7)	14% (1/7)	0% (0/7)	0% (0/7)	0% (0/7)	0% (0/7)
C57BL/6J
−/−	0% (0/12)	8% (1/12)	8% (1/12)	0% (0/12)	0% (0/12)	0% (0/12)
littermates	0% (0/38)	0% (0/38)	0% (0/38)	0% (0/38)	0% (0/38)	0% (0/38)