al. (2013) reported similar findings in a mouse model of AD where miRNA:mRNA positive correlations were more abundant than negative correlations [22]. It is unclear, however, whether these positive correlations represent direct miRNA upregulation of target mRNAs or secondary effects of the miRNA targeting mediating molecules. Therefore, we elected to focus on negative correlations, as the predominant (and canonical) effect of miRNAs on gene expression is through mRNA downregulation, which then manifests as negative miRNA:mRNA expression correlations [53].
