Crossing of these mice with the PS19 mouse model of tauopathy found that the R47H variant exacerbates damage and inflammation and does not function as a loss of function variant [18], unlike similar crosses of PS19 mice with the human BAC TREM2R47H model which actually protected against microglia activation and subsequent neurodegeneration [65], as did crosses with PS19 mice and Trem2 KO mice [66, 67]. The gene discussed is TREM2; the disease is tauopathy.