Facioaudiosymphalangism syndrome and growth acceleration associated with a heterozygous NOG mutation

Abstract

We report on a father and son with facioaudiosymphalangism syndrome, an alternative designation for multiple synostoses syndrome, type I. This syndrome includes synostosis, brachydactyly, craniofacial dysmorphic features, stapes fixation, hyperopia, and growth retardation. In contrast to the typical presentation, the height of the 10-year-old son was above the 97th centile from the age of 3.5 years and he had markers of an activated bone metabolism. The father and son had a novel heterozygous missense mutation c.696C > G, p.Cys232Trp, in the NOG gene. While not yet described in human NOG-related disorders, there is experimental evidence that suppression of noggin might accelerate osteogenesis, which could explain the phenotype in the family reported here.