Pre-eclampsia: Molecular events to biomarkers

Pre-eclampsia is a hypertensive disorder in pregnancy, which accounts for 10-15% of the maternal and perinatal mortality worldwide. Abnormal placental development and tissue hypoxia are its main etiologic factors. The present diagnostic methods of blood pressure monitoring and renal function evaluation are insufficient in the early detection of pre-eclampsia. Since molecular events portent well ahead of the disease onset, biomarker research for the early diagnosis of pre-eclampsia has recently generated ambitious clinical targets. However, no clinically validated biomarker has so far been reported for the prediction of pre-eclampsia. Therefore, this review takes stock of the current understanding of pre-eclampsia from a molecular biology perspective and critically evaluates the following diagnostic potentials claimed for the biomarkers: placental proteins, angiogenic markers, and cell-free fetal DNA (cffDNA) in maternal circulation. Though the emerging evidences in favor of the fetal-specific epigenetic marker, hypermethylated RASSF1A of cffDNA, are highlighted, it pitches for a broader strategy of 'combination biomarker approach' for the reliable forecasting and triaging of pre-eclampsia.