DOORS [deafness, onychodystrophy, osteodystrophy, intellectual disability (mental retardation), and seizures] syndrome can be caused by mutations in the <i>TBC1D24</i> and <i>ATP6V1B2</i> genes, both of which are involved in endolysosomal function. This evidence concerns the gene TBC1D24 and Nail dystrophy.