Brownjohn et al. first described the derivation of hPSC-derived microglia with Nasu-Hakola disease-associated TREM2 missense mutations and found that, although lower TREM2 levels were expressed by mutant cell-derived microglia, this did not affect considerably their phagocytic capacity or response to inflammatory stimuli [174]. Here, TREM2 is linked to Nasu-Hakola disease.