Within the epigenetics of AD, several genes are hypermethylated (APOE, MTHFR, MAPT, SORB3), and others are related to the production of the Aβ peptide (PSEN1, APP, PP2A, CREB5, S100A2, BACE) and remain hypomethylated. This evidence concerns the gene APOE and Alzheimer disease.