ASCL2 and fetal growth restriction: Targeted gene mutations of Ascl2, Hectd1, Htra1, and Pdcd5 lead to reduced junctional zones with IUGR, which is caused by a decrease in the number of SpT and GCs, as well as mislocalization of GCs (Oh-McGinnis et al. 2011; Sarkar et al. 2014; Hasan et al. 2015; Li et al. 2017).