AD-associated variants in Triggering Receptor Expressed in Myeloid cells 2 (TREM2) rendering microglia ineffective in Aβ plaque processing have been identified as second to the APOE ε4 allele genetic risk factor for sporadic AD, highlighting the importance of periplaque glia function in Aβ proteostasis and in arresting downstream cascade of AD neurodegeneration [4]. This evidence concerns the gene APOE and Alzheimer disease.