MedGen

Nonsyndromic hearing loss and deafness, DFNA3 is characterized by pre- or postlingual mild-to-profound progressive high-frequency sensorineural hearing impairment. Affected individuals have no other associated medical findings. [from GeneReviews]

Any autosomal recessive nonsyndromic deafness in which the cause of the disease is a mutation in the GJB6 gene. [from MONDO]

Nonsyndromic hearing loss and deafness (DFNB1) is characterized by congenital non-progressive mild-to-profound sensorineural hearing impairment. No other associated medical findings are present. [from GeneReviews]

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]

Hidrotic ectodermal dysplasia 2, or Clouston syndrome (referred to as HED2 throughout this GeneReview) is characterized by a triad of major clinical features including partial-to-complete alopecia, nail dystrophy, and palmoplantar hyperkeratosis. Sweating is preserved and there are usually no dental anomalies. Sparse scalp hair and dysplastic nails are seen early in life. In infancy, scalp hair is fine, sparse, and brittle. Progressive hair loss may lead to total alopecia by puberty. The nails may be milky white in early childhood; they gradually become dystrophic, thick, and distally separated from the nail bed. Palmoplantar keratoderma may develop during childhood and increases in severity with age. Associated features may include cutaneous hyperpigmentation (particularly over the joints) and finger clubbing. The clinical manifestations are highly variable even within the same family. [from GeneReviews]