Format

Send to

Choose Destination

Nonsyndromic Hearing Loss and Deafness, DFNB1.

Authors

Smith RJH1, Jones MKN1.

Source

GeneReviews® [Internet]. Seattle (WA): University of Washington, Seattle; 1993-2019.
1998 Sep 28 [updated 2016 Aug 18].

Author information

1
Department of Otolaryngology, University of Iowa Hospitals and Clinics, Iowa City, Iowa

Excerpt

CLINICAL CHARACTERISTICS:

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.

DIAGNOSIS/TESTING:

Diagnosis of DFNB1 depends on molecular genetic testing to identify biallelic pathogenic variants in GJB2 (sequence variants as well as variants in upstream cis-regulatory elements that alter expression of the gap junction beta-2 protein [connexin 26]).

MANAGEMENT:

Treatment of manifestations: Hearing aids; enrollment in appropriate educational programs; consideration of cochlear implantation for individuals with profound deafness. Surveillance: Surveillance includes annual examinations and repeat audiometry to confirm stability of hearing loss. Evaluation of relatives at risk: If both pathogenic variants have been identified in an affected family member, molecular genetic testing can be used to clarify the genetic status of an at-risk relative in childhood so that appropriate early support and management can be provided.

GENETIC COUNSELING:

DFNB1 is inherited in an autosomal recessive manner. In each pregnancy, the parents of a proband have a 25% chance of having a deaf child, a 50% chance of having a hearing child who is a carrier, and a 25% chance of having a hearing child who is not a carrier. When the GJB2 pathogenic variants causing DFNB1 are detected in an affected family member, carrier testing for at-risk relatives, prenatal testing for pregnancies at increased risk, and preimplantation genetic diagnosis are possible.

Copyright © 1993-2019, University of Washington, Seattle. GeneReviews is a registered trademark of the University of Washington, Seattle. All rights reserved.

Supplemental Content

Support Center