Genetically, NHD is caused by the set of heterogeneous mutations located in one of the two genes, DNAX-activation protein 12 (DAP12), alternatively named TYRO protein tyrosine kinase-binding protein (TYROBP) on chromosome 19q13.1 or triggering receptor expressed on myeloid cells 2 (TREM2) on chromosome 6p21.1 [5-7]. Here, TREM2 is linked to Nasu-Hakola disease.