Mutations in TREM-2 and DAP12 cause sclerotic lesions in the white matter of the central nervous system (CNS) in human polycystic lipomembranous osteodysplasia with sclerosing leukoencephalopathy (PLOSL)/Nasu-Hakola disease [39,40] and cause hypomyelinosis in mice [41]. The gene discussed is TREM2; the disease is Nasu-Hakola disease.