Placental gene expression and pre-eclampsia.

Pre-eclampsia and related syndromes, such as the HELLP (haemolysis, elevated liver enzymes and low platelets) syndrome, have a strong genetic component, although the nature, origin and recurrence rate of the genetic risks involved are not necessarily the same for each form of pregnancy-induced hypertension or population. This review addresses these items in the context of the recent understanding that (a) common diseases can be caused by common genetic variations, (b) the placental genotype can control the maternal phenotype, (c) epistasis and epigenetics are involved, and (d) a conserved pathway shared between organs is possible as well as a common, pathophysiological pathway is shared between syndromes.