PTPN11 and Milroy disease: Even though genes involved in lymphangiogenesis have been extensively studied in a mouse model [8], only a few homologous genes, including vascular endothelial growth factor receptor type 3 (VEGFR3), integrinα9 (ITGA9), Tyrosine-protein phosphatase non-receptor type 11 (PTPN11), and Forkhead box protein C2 (FOXC2), were reported in humans affected with hereditary lymphedema [5], [9].