PAPPA2 and preeclampsia: On the other hand, gene modules contributing to maternal or fetal diseases were also revealed under placenta transcriptomics of women with early-onset preeclampsia, such as LEP, PAPPA2, FLT1 to maternal blood pressure, and KIT, FBLN1, HSD17B1, CSH1 to fetal birth weight, and with late-onset preeclampsia, such as PAPPA, ADAM12, CYP19A1,CSH1, PSG3 to placental abnormal function (30, 32), the differences of which under different subtypes of preeclampsia reflected the heterogeneous etiology of this disease (28, 32).