Mutations in the genes encoding FOXC2, (FOXC2) CX47 (GJC2), and CX43 (GJA1) cause primary lymphedema in man (Fang et al., 2000; Ferrell et al., 2010; Ostergaard et al., 2011; Brice et al., 2013). Here, GJC2 is linked to primary lymphedema.