Xiang et al. performed global gene expression profiling of placental tissue from preeclamptic pregnancies and uncomplicated pregnancies to explore genes with differential expression. Placentas from normal and preeclamptic pregnancies were collected immediately after cesarean section, and two 1 cmᶾ fragments were dissected for microarray analysis.

Tissue Condition Samples
Test placenta preeclamptic pregnancy 5
Control placenta normal pregnancy 7
Gene Fold Change (log2) Significance Genus Species