KEGG functional enrichment analysis of these genes revealed that in addition to up-regulating signaling pathways related to reproduction, such as oocyte meiosis and oxytocin signaling pathway, some pathways related to nutrient metabolism were also significantly enriched (e.g., insulin signaling pathway, alcoholism, fatty acid degradation, and glycolysis/gluconeogenesis) (Fig. 1E). Here, INS is linked to alcohol dependence.