Interestingly, although the expression level of biglycan was increased in the skin of passage 3 DPC-CM-injected mice and was highly expressed in the induction of HFs, it was rarely expressed in the skin of passage 9 DPC-CM injected mice in this study, consistent with a prior demonstration that the DP contains a high level of biglycan [33], and suggests that biglycan is involved in key functions of HF biology. The gene discussed is BGN; the disease is hydrops fetalis.