Moreover, recent genome-wide association studies associated single nucleotide polymorphisms of genes highly enriched or exclusively expressed in myeloid cells (including Trem2, Tyrobp, Apoe, Ms4a, Abca7, Abi3, Spi1) with an altered risk of developing AD [20, 24, 25, 32, 64]. Here, TREM2 is linked to Alzheimer disease.