TREM2 is a microglia type I transmembrane protein that is a member of the immunoglobulin superfamily (Paloneva et al., 2002; Yeh et al., 2017; Kulkarni et al., 2021) and has been identified as an immune-associated receptor with high AD risk gene expression (Guerreiro et al., 2013; Slattery et al., 2014). This evidence concerns the gene TREM2 and Alzheimer disease.