MedGen

Ectodermal dysplasia-sensorineural deafness syndrome is characterised by hidrotic ectodermal dysplasia, sensorineural hearing loss, and contracture of the fifth fingers. It has been described in brother and sister born to consanguineous parents. The girl also presented with thoracic scoliosis. The mode of inheritance is likely to be autosomal recessive. [from ORDO]

GAPO syndrome is the acronymic designation for a complex of growth retardation, alopecia, pseudoanodontia (failure of tooth eruption), and progressive optic atrophy (Tipton and Gorlin, 1984). Ilker et al. (1999) and Bayram et al. (2014) noted that optic atrophy is not a consistent feature of the disorder. [from OMIM]

DFNX2, also known as DFN3, is an X-linked recessive disorder characterized by progressive conductive and sensorineural hearing loss and a pathognomonic temporal bone deformity that includes dilatation of the inner auditory canal and a fistulous connection between the internal auditory canal and the cochlear basal turn, resulting in a perilymphatic fluid 'gusher' during stapes surgery (summary by de Kok et al., 1995 and Song et al., 2010). See also choroideremia, deafness, and mental retardation (303110), a contiguous gene deletion syndrome involving the POU3F4 and CHM (300390) genes on Xq21; isolated choroideremia (303100) is caused by mutation in the CHM gene. [from OMIM]

A deficiency in biotin through either inherited or acquired causes. [from MONDO]

The presence of sensorineural deafness with late onset. [from HPO]

A rare mitochondrial disease with characteristics of a variable clinical phenotype with the core features of optic atrophy, ataxia and hypotonia. Additional common manifestations include global developmental delay with or without regression, neuropathy, spasticity, and microcephaly, less frequently seizures, movement disorder, hearing loss and respiratory failure. Brain imaging may show abnormalities of the corpus callosum, basal ganglia and midbrain, cerebral or cerebellar atrophy, or white matter abnormalities. The condition is frequently fatal at an early age. [from SNOMEDCT_US]

If untreated, young children with profound biotinidase deficiency usually exhibit neurologic abnormalities including seizures, hypotonia, ataxia, developmental delay, vision problems, hearing loss, and cutaneous abnormalities (e.g., alopecia, skin rash, candidiasis). Older children and adolescents with profound biotinidase deficiency often exhibit motor limb weakness, spastic paresis, and decreased visual acuity. Once vision problems, hearing loss, and developmental delay occur, they are usually irreversible, even with biotin therapy. Individuals with partial biotinidase deficiency may have hypotonia, skin rash, and hair loss, particularly during times of stress. [from GeneReviews]