Published 01/07/2015
Pendred Syndrome
Sequencing of the SLC26A4 gene
Specimen requirements: |
2-4 ml of blood with anticoagulant EDTA
2 µg DNA in TE, AE or pure sterile water at 100-250 ng/µl
The A260/A280 ratio should be 1.8-2.0. DNA sample should be run on an agarose gel as a single band, showing no degradation, alongside with a quantitative DNA marker. |
Deletion/duplication analysis of the SLC26A4 gene
Specimen requirements: |
2-4 ml of blood with anticoagulant EDTA
1 µg DNA in TE, AE or pure sterile water at 100-250 ng/µl
The A260/A280 ratio should be 1.8-2.0. DNA sample should be run on an agarose gel as a single band, showing no degradation, alongside with a quantitative DNA marker. |
Indications for genetic testing:
- Confirmation of clinical diagnosis
- Carrier status detection of known mutation
- Genetic counseling
Pendred syndrome is an autosomal recessive condition characterized by bilateral sensorineural hearing impairment, vestibular and cochlear abnormalities, temporal bone abnormalities and goiter. Considerable phenotypic variability is found even within the same family. Sensorineural hearing loss is usually congenital, severe to profound and non-progressive. However, hearing loss may be later onset and progressive in some patients.
Pendred syndrome, as well as nonsyndromic hearing loss and deafness (DFNB4) show similar phenotypic spectrum. DFNB4 is characterized by nonsyndromic sensorineural hearing loss, vestibular dysfunction, enlarged vestibular aqueduct but normal thyroid function.
For further information:
Alasti F et al. Pendred Syndrome/DFNB4. GeneReviews® 1998 Sept 28 (Updated 2014 May 29)
Napiontek U et al. Intrafamilial variability of the deafness and goiter phenotype in Pendred syndrome caused by a T416P mutation in the SLC26A4 gene. J Clin Endocrinol Metab. 2004;89:5347–51.
Reardon W, Trembath RC: Pendred syndrome. J Med Genet 1996; 33: 1037–40.
Stinckens C et al. Fluctuant, progressive hearing loss associated with Menière like vertigo in three patients with the Pendred syndrome. Int J Pediatr Otorhinolaryngol. 2001;61:207–15.