Intrauterine growth restriction and placental gene expression in severe preeclampsia, comparing early-onset and late-onset forms.

Objective: To evaluate placental gene expression in severe early- or late-onset preeclampsia with intrauterine growth restriction compared to controls. Study design: Chorionic villus sampling was conducted after cesarean section from the placentas of five women with early-or late-onset severe preeclampsia and five controls for each preeclampsia group. Microarray analysis was performed to identify gene expression differences between the groups. Results: Pathway analysis showed over-representation of gene ontology ( GO) biological process terms related to inflammatory and immune response pathways, platelet development, vascular development, female pregnancy and reproduction in early-onset preeclampsia. Pathways related to immunity, complement and coagulation cascade were overrepresented in the hypergeometric test for the Kyoto Encyclopedia of Genes and Genomes ( KEGG) database. Ten genes ( ABI3BP, C7, HLA-G, IL2RB, KRBOX1, LRRC15, METTL7B, MPP5, RFLNB and SLC20A) had a >=+/- 1 fold expression difference in severe early-onset preeclampsia group compared to early controls. There were 362 genes that had a >=+1 fold expression difference in severe earlyonset preeclampsia group compared to late-onset preeclampsia group including ABI3BP, C7, HLA-G and IL2RB. Conclusion: There are significant differences in placental gene expression between severe early- and late-onset preeclampsia when both are associated with intrauterine growth restriction. ABI3BP, C7, HLA-G and IL2RB might contribute to the development of early form of severe preeclampsia.