SLC9A6 encodes a Na+/H+ exchanger localized to early endosomes that is essential for maintaining endosomal-lysosomal homeostasis.7,12 Growing evidence implicates haploinsufficiency of lysosome-related genes as a common mechanism in neurodegenerative diseases.8-11 NDPACX appears to exemplify this category and represents a novel form of neurodegeneration related to endosomal-lysosomal dysfunction. Here, SLC9A6 is linked to neurodegenerative disease.