A role for microRNAs in the epigenetic control of sexually dimorphic gene expression in the human placenta

Aim:The contribution of miRNAs as epigenetic regulators of sexually dimorphic gene expression in the placenta is unknown.Materials & methods:382 placentas from the extremely low gestational age newborns (ELGAN) cohort were evaluated for expression levels of 37,268 mRNAs and 2,102 miRNAs using genome-wide RNA-sequencing. Differential expression analysis was used to identify differences in the expression based on the sex of the fetus.Results:Sexually dimorphic expression was observed for 128 mRNAs and 59 miRNAs. A set of 25 miRNA master regulators was identified that likely contribute to the sexual dimorphic mRNA expression.Conclusion:These data highlight sex-dependent miRNA and mRNA patterning in the placenta and provide insight into a potential mechanism for observed sex differences in outcomes.