PTGFRN and fetal growth restriction: In current study, among the downregulated genes in skeletal muscles from IUGR fetuses, calpain 2 (CAPN2), EH-domain containing 1 (EHD1), prostaglandin F2 receptor negative regulator (PTGFRN), and vasohibin-2 (VASH2) are involved in myoblast fusion (Figure 5).