Dominant heterozygous mutations in the forkhead family transcription factor FOXC2 are associated with human lymphedema, venous insufficiency and varicose veins (Bell et al., 2001; Brice et al., 2002; Fang et al., 2000; Lyons et al., 2017; Mellor et al., 2007, 2011). The gene discussed is FOXC2; the disease is lymphedema.