Recent mechanistic studies have demonstrated that AD‐related neurofibrillary tau tangles first accumulate in the Cornu Ammonis 1 (CA1) before propagating to adjacent subfields, such as the subiculum and CA2/3 Alzheimer's [4, 5], whereas amyloid‐β pathology preferentially targets the CA4/dentate gyrus (DG) region and coincides with the early collapse of adult hippocampal neurogenesis in the DG [6]. This evidence concerns the gene MAPT and Alzheimer disease.