Placental Genetic Variants in the Upstream Region of the FLT1 Gene in Pre-eclampsia

Characterization of the MG828507 lncRNA Located Upstream of the FLT1 Gene as an Etiology for Pre-Eclampsia

Background: FLT1 is one of the significantly overexpressed genes found in a pre-eclamptic placenta and is involved with the etiology of this disease. Methods: We conducted genome-wide expression profiling by RNA-seq of placentas from women with pre-eclampsia and those with normotensive pregnancy. Results: We identified a lncRNA gene, MG828507, located ~80 kb upstream of the FLT1 gene in a head-to-head orientation, which was overexpressed in the pre-eclamptic placenta. MG828507 and FLT1 are located within the same topologically associated domain in the genome. The MG828507 mRNA level correlated with that of the FLT1 in placentas from pre-eclamptic women as well as in samples from uncomplicated pregnancies. However, neither the overexpression nor knockdown of MG828507 affected the expression of FLT1. Analysis of pre-eclampsia-linking genetic variants at this locus suggested that the placental genotype of one variant was associated with the expression of MG828507. The MG828507 transcript level was not found to be associated with maternal blood pressure, but showed a relationship with birth and placental weights, suggesting that this lncRNA might be one of the pivotal placental factors in pre-eclampsia. Conclusion: Further characterization of the MG828507 gene may elucidate the etiological roles of the MG828507 and FLT1 genes in pre-eclampsia in a genomic context.