Autosomal dominant deafness-onychodystrophy syndrome (Orphanet_79499, an Orphanet rare-disease nomenclature id) can be described as follows. Dominant deafness-onychodystrophy (DDOD) syndrome is a multiple congenital anomalies syndrome characterized by congenital hearing impairment, small or absent nails on the hands and feet, and small terminal phalanges. Also known as: DDOD syndrome.