RNAseq in mouse models of AD has been used to identify neuroprotective “disease-associated microglia” (DAM) as described by Keren-Shaul et al. (2017) and the “microglial neurodegenerative phenotype” (MGnD) (Krasemann et al., 2017)—both of which are characterised by TREM2 activation and associated with increased APOE expression. This evidence concerns the gene TREM2 and Alzheimer disease.