FOXD3 Background Information Embryonic stem cells require the forkhead transcriptional regulator FoxD3 for survival. Following gastrulation, FoxD3 generally gets downregulated, except in the neural crest. A variety of growth factors induce FoxD3 expression, including FGF8 and SNAIL, maintaining the effected cells in an undifferentiated state. Thus defects in FoxD3 induction may cause premature differentiation and/or migration-asociated birth defects.