We also performed RT-PCR analyses in FACS-isolated HF-SCs (Figure 4C) and observed an increase in their number and in the relative mRNA expression levels of the Wnt signaling related genes Lef1 [68],[69], and mOVO1 [70] and Axin2 [71] starting from T2, without any changes in the expression levels of the HF-inhibitory proteins BMP2 and BMP4 (Figure 4D) [18],[21],[25],[72]. This evidence concerns the gene BMP4 and hydrops fetalis.