Of them, pathways with the top 10 enrichment ratio (the observed number of genes suggestively associated with PPD to the expected number of genes based on the KEGG pathway database) included long‐term depression, salivary secretion, gonadotropin‐releasing hormone (GnRH) signaling, glutamatergic synapse, oxytocin signaling, cell adhesion molecules (CAMs), Rap1 signaling, and cancer‐related pathways (Fig. 2). The gene discussed is GNRH1; the disease is cancer.