Although the role of TREM2 expression on microglial function in the context of Aβ and tau is still up for debate (Ulrich et al., 2014, Melchior et al., 2010, Kleinberger et al., 2014), the importance of GWAS for furthering both the basic understanding of AD as well as the importance in elucidating new therapeutic avenues to pursue is unequivocal. This evidence concerns the gene TREM2 and Alzheimer disease.