WLS and Pulmonary hemorrhage: Interestingly, it has been reported that blockade of Wnt ligand production from fetal lung epithelial cells by deleting Wntless (or Gpr177) also results in pulmonary hemorrhage, but such lesion occurs at a late developmental stage (neonatal) with less severity (interstitial capillary leakage without destruction of saccular structure) [30, 31].