(A, B) The AVE marker Hhex is expressed normally in e7.5 mutant embryos (n=4). (C, D) Cer1, which marks the AVE, is expressed normally in mutant embryos (n=2). (E, F) Cer1, an early marker of the definitive endoderm, is expressed normally in stage-matched mutant embryos (n=5). (G,H) Chordin is expressed normally in the posterior axial mesendoderm in stage-matched mutant embryos (n=5). Scale bars: 0.25mm.