Previously, our group reported inducible LEC-specific deletion of Foxc2 via Prox1-CreERT2 (Bazigou et al., 2011) at P4 was shown to significantly reduce total valve number in mesenteric lymphatic collecting vessels and a subset of Foxc2 mutants presented chylous ascites and chylothorax beginning as early as 3 days after tamoxifen treatment with eventual fully penetrant mortality (Sabine et al., 2015). This evidence concerns the gene PROX1 and Chylothorax.