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[Genetics of congenital deafness]
Víctor Faundes1, Rosa Andrea Pardo, Silvia Castillo Taucher
1Sección de Genética, Departamento de Medicina, Hospital Clínico Universidad de Chile, Santiago, Chile. vfaundes@ug.uchile.cl
Medicina Clinica
|April 28, 2012
Summary
Congenital deafness, present at birth, is a common sensorineural disorder often caused by genetics. Diagnosis aids in managing potential syndromes and provides genetic counseling for families.
Area of Science:
- Genetics and Audiology
- Pediatric Medicine
Context:
- Congenital deafness is hearing loss present at birth, preceding speech development.
- It is the most common sensorineural disorder in developed nations, affecting 1-3 per 1,000 newborns.
- Over 50% of congenital deafness cases have genetic origins.
Purpose:
- To outline the classification and genetic basis of congenital deafness.
- To emphasize the importance of a multidisciplinary diagnostic approach.
- To highlight the goals of diagnosis, including syndrome prediction, management, and genetic counseling.
Summary:
- Congenital deafness is classified as syndromic (associated with other conditions, ~30% of cases) or non-syndromic (~70%).
- Non-syndromic deafness has varied inheritance patterns: 75-85% autosomal recessive, 15-24% autosomal dominant, and 1-2% X-linked.
- Over 400 syndromes include deafness as a feature.
Impact:
- Facilitates early identification of syndromic deafness, enabling timely intervention and management.
- Provides crucial information for genetic counseling, empowering families with knowledge about inheritance patterns.
- Establishes a framework for coordinated specialist care in evaluating children with hearing loss.
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