Hierarchical clustering of differentially expressed genes in placentas from healthy pregnancies and women with ICP. (A) Clinical features of healthy women and women with mild or severe ICP. 10 pregnant women were recruited for each group, and data are shown as mean ± s.d. (n = 10). (B) Hierarchical clustering of genes whose expression was altered by more than 1.5-fold in ICP placentas comparing to those in healthy placentas. Red and green represent individual genes that were differentially up-regulated or down-regulated, respectively.