Placental gene expression profiling for the identification of clinically relevant subclasses of human preeclampsia. Homo sapiens

Preeclampsia (PE) is a complex, heterogeneous disorder of pregnancy, demonstrating considerable variability in observed maternal symptoms and fetal outcomes. We hypothesized that this heterogeneity is due to the existence of multiple molecular forms of PE. To address our hypothesis, we created a large (N=330) human placental microarray data set consisting of seven previously published studies (GSE30186, GSE10588, GSE24129, GSE25906, GSE43942, GSE4707, and GSE44711) and 157 highly annotated samples from a BioBank (below). Applying unsupervised clustering to this combined data set revealed multiple distinct molecular groups of placentas, including three clinically relevant potential origins of PE based on gene expression and correlating patient records. Overall design: A total of 80 PE placentas and 77 non-PE placentas, representing a range of clinical presentations, were purchased from a BioBank. When combined with the previously-published data sets, we had access to and analyzed gene expression data for 157 PE placentas and 173 non-PE placentas.