TREM2 and Alzheimer disease: Among them, coding variants in the triggering receptor expressed on myeloid cells 2 (TREM2) increase the risk for late‐onset AD as much as the apolipoprotein ε4 allele (Guerreiro et al, 2013; Jonsson & Stefansson, 2013; Jonsson et al, 2013; Rayaprolu et al, 2013; Borroni et al, 2014; Cuyvers et al, 2014).