The clinical characteristics of DDOD syndrome are:
- Congenital severe to profound sensorineural hearing loss without inner ear malformation.
- Dystrophic or absent nails, absence of all toenails, nails of thumbs and little fingers.
- Dysplasia of the index finger nails, middle finger nails and ring finger nails.
- Absence of the middle phalanx in the fifth fingers.
- Conical and hypoplastic teeth.
- Subtle learning and memory disorder.