Fig. 1. Deletion of mouse Wnt7b results in hypoplastic lungs. (A) Strategy to remove Wnt7b from only the embryo proper. (B) Mutant lungs are 50% smaller than wild-type at E18.5. The overall mass of the embryo is unchanged. (C) Mutant lungs are 75% smaller than wild-type at E14.5. The overall mass of the embryo is unchanged. (D) Control and mutant lungs at E12.5. E-cadherin staining shows grossly normal lobulation in mutant lungs. However, the right medial lobe bronchus (^*) of the Wnt7b mutant lung emanates from the cephalic lobe bronchus.