Downregulated genes in old Tet1–/– oocytes were enriched in insulin signaling pathway, Parkinson’s disease, pathways in cancer and sphingolipid signaling pathway, and genes upregulated in old Tet1–/– oocytes enriched in spliceosome, choline metabolism in cancer, and phospholipase D signaling pathway (Figure 3B). This evidence concerns the gene TET1 and cancer.