Gene Ontology (GO) analysis showed that module 1 genes were enriched in positive regulation of cell death (Btg2, Cav2, and Dusp1) and oxidative phosphorylation (Atp5c1, Cox17, and Ndufa1) (Fig. 2D; Table S3), consistent with the previous discovery that the inhibition of mitochondrial oxidative phosphorylation stimulated the anagen phase and accelerated HF regeneration (Kondo et al., 2002). Here, BTG2 is linked to hydrops fetalis.