ANGPT2 and lymphedema: ANGPT2 disrupts angiogenesis in the developing embryo by antagonising the effects of angiopoietin-1 and Tie2.25 In mice, homozygous deletion of ANGPT2 or treatment with Angpt2-blocking antibodies results in morphologically and functionally abnormal lymphatics and neonatal death.26 Pathogenic ANGPT2 variants identified in lymphoedema in humans and studied in mice affect protein function via haploinsufficiency or a dominant-negative mechanism.