• provided adequate access to food and water homozygotes are viable (J:107668)

• development of the forelimb stylopod elements is severely impaired; however development of the forelimb zeugopd elements is similar to wild-type mice

• virtually absent at birth with only a small abnormal dorsal piece remaining that does not span the axis of the limb

• development of the hindlimb stylopod elements is severely impaired

• virtually absent at birth with only a tiny cartilage analage which lacks ossification is seen; in adults ossification is seen but little bone growth occurs

• the hindlimb zeugopod is also shorter

• markedly bowed

• virtually absent at birth with only a small abnormal dorsal piece remaining that does not span the axis of the limb

• virtually absent at birth with only a tiny cartilage analage which lacks ossification is seen; in adults ossification is seen but little bone growth occurs

• markedly bowed

• hypertrophic chondrocytes eventually appear in the humerus but are in abnormal asymmetric locations blocking formation of the growth plate

• at E12.5, the humerus and femur cartilages are already significantly shorter (by about 50%) than in wild-type

• by E14.5 the humerus and femur cartilage malformation is as severe as in newborns

• chondrocyte differentiation in the humerus is impaired with markers for immature cells (Col2a1) still present at E18.5 and expression of later markers greatly decreased or absent