Homozygous mutations in either TREM2 or its adapter protein DNAX-activating protein of 12 kDa (DAP12) result in Nasu-Hakola disease (NHD), a progressive neurodegenerative disorder with massive gliosis and demyelination in the subcortical white matter (12, 13). This evidence concerns the gene TYROBP and Nasu-Hakola disease.