MT-ND2 and Alzheimer disease: Interestingly, among these 158 significant DMCs, which mainly covered D-Loop, mt-ND1, mt-ND2, mt-ND4, mt-ND5, mt-CO1, mt-CYB, mt-RNR1, and mt-RNR2 regions, 146 DMCs (92.4%) were found to be hypomethylated in AD (Figure 2B).