A molecular transition revealed at mid-gestation in the fetal placenta. The transition at mid-gestation is global, encompassing 3543 genes in the placenta and 1108 genes in the decidua that change significantly over time (FDR < 0.1% using SAM [Tusher et al. 2001] and having a minimum 1.5-fold change within a 2-d time period). Genes that change significantly during placental development were clustered using dCHIP (Li and Wong 2001a, b). Expression values for each gene across all samples were linearly scaled to have a mean of 0 and standard deviation of 1; red indicates expression greater than the mean; and blue indicates expression below the mean. (A) Clustergram of 3543 genes that change significantly in the placenta. (B) Clustergram of 1108 genes that change significantly in the decidua. Genes in Clusters labeled D are highly expressed in the developing placenta (e8.5–e13.5), while genes in Clusters labeled M are highly expressed in the mature placenta (e13.5–P0).
