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GTR Home > Conditions/Phenotypes > X-linked mixed hearing loss with perilymphatic gusher


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]

Available tests

53 tests are in the database for this condition.

Check Related conditions for additional relevant tests.

Genes See tests for all associated and related genes

  • Also known as: BAPS, CX26, DFNA3, DFNA3A, DFNB1, DFNB1A, HID, KID, NSRD1, PPK, GJB2
    Summary: gap junction protein beta 2

  • Also known as: CX30, DFNA3, DFNA3B, DFNB1B, ECTD2, ED2, EDH, HED, HED2, GJB6
    Summary: gap junction protein beta 6

  • Also known as: BRAIN-4, BRN-4, BRN4, DFN3, DFNX2, OCT-9, OTF-9, OTF9, POU3F4
    Summary: POU class 3 homeobox 4

Clinical features


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