
-   TREM2 deficiency results in impaired clearance of apoptotic neurons might be responsible for the brain degeneration observed in patients with Nasu-Hakola disease, which is a recessively inherited disease due to functional deficiency of TREM2 or DAP12 [PMID: 15728241, PMID: 11402114, PMID: 12370476, PMID: 12913093].
-   Polymorphisms in the *Trem2* gene have been linked with Alzheimer's disease [PMID: 23150934, PMID: 23150908]. Exon 2 of Trem2 (rs75932628-T, Arg47His) is associated with 3-fold higher risk of Alzheimer's disease onset [PMID: 24663666, PMID: 28714976].
-   TREM-2 was significantly higher in the inflamed mucosa of patients with IBD than controls. TREM-2 knockout mice developed less severe colitis than wild-type mice. This suggests a pro-inflammatory role of TREM-2 in the gut [PMID: 23108068]. Efficient colonic mucosal wound repair requires Trem2 signaling [PMID: 19109436].
-   Mutations in TREM2 lead to pure early-onset dementia without bone cysts [PMID: 18546367].
