Vitamin D receptor polymorphisms in hypertensive disorders of pregnancy

Hypertension is the most common medical disorder in pregnancy, and a leading cause of maternal and neonatal morbidity and mortality. Vitamin D endocrine system has important influence on immune modulation and endothelial function, which play a role in preeclampsia (PE) and gestational hypertension (GH). Vitamin D receptor (VDR) is present in a large variety of cell types, including placental cells. We examined whether there is an association between VDR polymorphisms (FokI, ApaI and BsmI) with PE or with GH. Restriction fragment length polymorphism techniques were used to genotype 529 pregnant (154 with GH, 162 with PE, and 213 healthy pregnant-HP). VDR haplotype frequencies were inferred using the PHASE 2.1 program. We found similar genotype distributions for the three VDR polymorphisms in both PE and GH groups compared with the HP group (all P > 0.05). In parallel with these findings, the VDR haplotype frequency distribution was similar in both PE and GH groups compared with the HP group (all P > 0.05). Our results showing no significant association between VDR polymorphisms or haplotypes with PE or GH suggest that genetic variations in VDR do not predispose to hypertensive disorders of pregnancy.