YAP1 and congenital diaphragmatic hernia: To determine whether Yap activation and distal lung basal cell expansion also occurred in human TO, we analyzed lung specimens from two infants who died shortly after birth with congenital high airway obstruction (CHAOS) (gestational ages, 34 and 36 weeks), three infants who died either before or shortly after delivery following FETO for CDH, and two lung specimens of infants who died of non-pulmonary causes at those same ages.