NOTCH2 and Alzheimer disease: The Protein–protein interaction (PPI) network showed that these significant m6A methylation regulators could interact with some of the key AD genes directly or indirectly, as shown in Figure 7A. In addition, the key AD genes, NOTCH2 and NME1, were closely related to m6A regulators and might be the important targets in m6A methylation during the progression of AD.