gms | German Medical Science

76. Jahresversammlung der Deutschen Gesellschaft für Hals-Nasen-Ohren-Heilkunde, Kopf- und Hals-Chirurgie e. V.

Deutsche Gesellschaft für Hals-Nasen-Ohren-Heilkunde, Kopf- und Hals-Chirurgie e. V.

04.05. - 08.05.2005, Erfurt

Evidence of a novel Gene for Enlarged Vestibular Aqueduct Syndrome

Meeting Abstract

  • corresponding author Ralf Birkenhäger - Department of Otorhinolaryngology and Head and Neck Surgery, University Hospital Freiburg, Freiburg
  • Ariane Julia Zimmer - Department of Otorhinolaryngology and Head and Neck Surgery, University Hospital Freiburg, Freiburg
  • Antje Aschendorff - Department of Otorhinolaryngology and Head and Neck Surgery, University Hospital Freiburg, Freiburg
  • Thomas Klenzner - Department of Otorhinolaryngology and Head and Neck Surgery, University Hospital Freiburg, Freiburg
  • Jörg Schipper - Department of Otorhinolaryngology and Head and Neck Surgery, University Hospital Freiburg, Freiburg

Deutsche Gesellschaft für Hals-Nasen-Ohren-Heilkunde, Kopf- und Hals-Chirurgie. 76. Jahresversammlung der Deutschen Gesellschaft für Hals-Nasen-Ohren-Heilkunde, Kopf- und Hals-Chirurgie e.V.. Erfurt, 04.-08.05.2005. Düsseldorf, Köln: German Medical Science; 2005. Doc05hno500

Die elektronische Version dieses Artikels ist vollständig und ist verfügbar unter: http://www.egms.de/de/meetings/hno2005/05hno123.shtml

Veröffentlicht: 22. September 2005

© 2005 Birkenhäger et al.
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Gliederung

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Background: Pendred syndrome [MIM 274600], an autosomal-recessive disorder is characterized by sensorineural deafness and goiter. The deafness is associated with temporal bone abnormalities ranging from isolated enlargement of the vestibular aqueduct (EVA, LAV) to Mondini dysplasia, a more complex malformation that also includes cochlear hypoplasia. One gene is located on Chromosome 7q31, is composed of 21 exons that encode a 780 amino acid protein. This gene product, a transmembrane protein, is called pendrin. Pendrin is expressed in the non-sensory epithelia of the inner ear, renal cortical collecting ducts and proximal tubule of the kidney. Functional studies in Xenopus laevis oocytes and Sf9 cells have shown that pendrin is a transporter of iodide and chloride. In this study we analyzed several multiplex families with EVA and hearing loss to distinguish between the Pendred- and EVA-Syndrome [MIM 603545].

Methods: Linkage analysis was undertaken using Microsatellites markers for the SLC26A4 gene locus at Chromosome 7q31. Individual exon and intron transitions of the SLC26A4/PDS gene of patients were PCR amplified. Direct automatic sequencing of fragments was performed with the same primers.

Results: In the analyzed patient collective with Pendred syndrome and/or enlargement of the vestibular aqueduct, in 30 % of the cases no mutation could be detected. These patients carry potential mutations in regulatory domains such as promotor regions, or alternatively the possibility of a distinct locus for a gene of autosomal recessive deafness with enlarged vestibular aqueduct. With linkage analysis of these families it was possible to identify a potential gene which is, in addition to the SLC26A4/PDS gene, responsible for the development of the Enlarged Vestibular Aqueduct Syndrome.

Conclusions: Our results indicate evidences of a second gene which is involved in the development of the Enlarged Vestibular Aqueduct Syndrome. In the future all patients with EVA and without mutations in the SLC26A4 gene will be analyzed of alterations in the second gene. The investigation of the structure and the function of this gene may contribute to a better understanding of the origin of the Enlarged Vestibular Aqueduct Syndrome.