Despite the fact that there was no difference in HF density between genotypes, examination of hfDSCs after third anagen (~P60) revealed a significant decline in the total number of HFs containing YFP+ve cells in Pdgfrαflox/flox animals (50.5 ± 9.90%) in comparison to the Pdgfrα+/+ (86.8 ± 4.37%) (p < 0.05) (Fig. 2a–f). This evidence concerns the gene PDGFRA and hydrops fetalis.