Relationships between Dicer 1 polymorphism and expression levels in the etiopathogenesis of preeclampsia.

Preeclampsia (PE) is a pregnancy-specific complication which is a major cause of maternal and fetal morbidity and mortality. Recent studies have shown the aberrant expression of microRNAs (miRNAs) in the placenta of patients with PE. Dicer1 is a key enzyme in the generation of small noncoding RNAs including miRNAs. The aim of this study is to investigate the relationship between maternal and placental Dicer1 rs3742330 polymorphism and placental Dicer1 mRNA expression in PE and normotensive pregnant women. The blood and placenta of PE pregnant and normotensive pregnant women were collected after delivery. Dicer1 rs3742330 polymorphism was genotyped using PCR-RFLP method. The mRNA expression levels were measured using quantitative real time PCR. The maternal Dicer1 rs3742330 polymorphism was not associated with PE or PE severity; however, the placental Dicer1 rs3742330 AG genotype was associated with two fold higher risk of PE and three fold higher risk of severe PE (P = 0.018 and P = 0.005, respectively). The relative mRNA expression of Dicer1 gene in the placenta did not differ between the two groups. In addition, the relative mRNA expression of Dicer1 gene was significantly lower in the placenta of women with rs3742330 AG+GG genotypes in the total population (P = 0.028) and PE women (P = 0.004), but not in the control group. In conclusion, there was a relationship between placental but not maternal Dicer1 rs3742330 polymorphism and PE. There was no difference in Dicer1 mRNA expression between the PE and control groups; however, it was significantly lower in the placenta of women with rs3742330 AG+GG genotypes.