CDKN1A and Alzheimer disease: We compared the proportion of cells expressing senescence markers (p16, p21, GLB1 and γ-H2AX) in each cluster and found that cluster-9 representing microglia (Iba1+) was both enriched for β-amyloid (Fig. 1d) and had an increased proportion of senescent nuclei expressing GLB1, p21 and γ-H2AX in AD compared to NDC in MTG following a similar trend as we observed in Cohort-1 (p value < 0.1, Fig. 1e, supplementary Fig. 2a).