The erythroid phenotype is shaped by differential Hox gene expression. (A) qRT-PCR analysis of members of HoxA and B cluster genes along with Cdx genes in Cdx2 and Cdx4 transduced cells of primary CFC. ΔCt values were obtained by normalizing to Gapdh, and fold expression compared with empty vector was calculated. The diagram shows average expression levels of 3 independent experiments ± SD. Vector control transduced cells negative for Cdx2 expression; *significant difference between vector control, Cdx2 and Cdx4, respectively. (B) Expression of Hox cluster genes in diseased Cdx4 transplanted mice. Mice that died of an acute leukemia after transplantation with Cdx2 or Cdx4 transduced BM were analyzed for their expression of Hox genes by TaqMan qRT-PCR. Multiple tests using Holm-Sidak method were performed on each gene. Cdx2, Cdx4, Hoxb3 and Hoxb4 were significantly differentially expressed. *Significant difference between Cdx2 and Cdx4, respectively.