KEGG pathways of hyper-methylated genes were mainly enriched in “Pathways of neurodegeneration - multiple disease”, “Alzheimer disease”, “Amyotrophic lateral sclerosis”, “Huntington disease”, “cAMP signaling pathway”, “Parkinson disease”, “Adrenergic signaling in cardiomyocytes”, “Oxytocin signaling pathway”, “Ras signaling pathway” and “Calcium signaling pathway” (Figure 3C; Supplementary Table S4). The gene discussed is OXT; the disease is Parkinson disease.