Variants linked to AD affect the expression of TREM2, its trafficking to the cell surface, its shedding, its ligand binding, and its downstream signaling (Jiang et al., 2016; Jin et al., 2014; Olive et al., 2020; Parhizkar et al., 2019; Roussos et al., 2015; Song et al., 2017). The gene discussed is TREM2; the disease is Alzheimer disease.