A Danish family with dominant deafness-onychodystrophy syndrome

The rare hereditary disorder "dominant deafness and onychodystrophy (DDOD) syndrome" (OMIM 124480) has been described in a few case reports. No putative DDOD gene or locus has been mapped and the cause of the disorder remains unknown.

We present here three male family members in three generations with sensori-neural deafness, onychodystrophy and brachydactyly inherited via autosomal dominant transmission. The family members presented with absent fingernails on the first and fifth digits. As to the feet, there were absent nails on second to fifth toes in two family members, whereas the third family member only had absent nails on the fifth toe. The proband had late dentition and his father a history of late dentition, but otherwise the teeth appeared normal. Comparative genomic hybridization array analysis (Agilent 400k oligoarray) of the proband did not detect any copy number variation.

This Danish family fits within the spectrum of dominant deafness and onychodystrophy syndrome and further characterises this rare disorder.