Thereby, our results might suggest that a series of genes affected by IUGR were located in chromosome X. Enrichment analysis of DMR-related genes (DMRGs) by Gene ontology (GO) server based on molecular function indicated that majority of these genes encoded binding proteins that may function as key regulatory factors, such as transcription factors or signaling proteins (Fig. 2d). This evidence concerns the gene KLK7 and fetal growth restriction.