The reduced tau pathology corresponded with 60% lower Cdkn2a expression (p = 0.0041, Figure 4a), decreased SASP (Supporting Information Figure S4), and decreased brain atrophy (tauNFT‐Mapt0/0: 0.4058 ± 0.009 vs. age‐matched tauNFT‐Maptwt/wt: 0.3451 ± 0.0116; 17.5% difference, p = 0.0143, Figure 4b). Here, MAPT is linked to Brain atrophy.