Firstly, different species may intrinsically regulate ANG-1 and TIE-2 differently through development [40]: hypoplastic human fetal lung associated with a range of conditions including CDH showed minimal gestational change in ANG-1 but a fall in TIE-2 [41]; in baboon lung both ANG-1 and TIE-2 mRNA levels have been reported to rise during gestation [42]; in a murine CDH model, raised ANG-1 protein levels were transiently observed in late gestation lung but, in keeping with our observations, normal levels returned after birth [26]. Here, TEK is linked to congenital diaphragmatic hernia.