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Laboratory Test Directory

Pendrin (SLC26A4) Gene Sequencing, Pendred Syndrome

Components

Name Method Department Units
Pendrin (SLC26A4) Gene Sequencing,Pendred Syndrome Polymerase chain reaction (PCR)
Analysis of the entire coding region: Sequence analysis
Sanger sequencing
DNA extraction
Molecular Genetics

Specimen Requirements

Whole blood

Container Type Container Size Specimen Volume
Preferred

Purple tube (EDTA)

4 mL 4 mL-8 mL
Stability

Room temperature - 24 hour(s)
Refrigerated - 72 hour(s)

Specimen Preparation

  • Do not centrifuge
  • Do not freeze
  • Transport to laboratory as soon as possible

Reasons for Rejection

  • Centrifuged specimen
  • Collected in tube with gel separator
  • Frozen specimen
  • Clotted specimen

Comments

Please click on the Lab Form Link in the Forms Section to print and complete the Genetic Test Requisition Form. Submission of completed Genetic Test Requisition Form is required, and submission of informed consent form is recommended.

Mutations in both alleles of the SLC26A4 gene can cause autosomal recessive syndromic hearing loss (Pendred syndrome) and autosomal recessive non-syndromic hearing loss (DFNB4). A clinical diagnosis of Pendred syndrome is made when a patient presents with congenital sensorineural hearing loss, thyroid changes (abnormal perchlorate testing, elevated serum thyroglobulin levels, or goiter), and dilatation of the vestibular aqueducts with or without cochlear hypoplasia. Most persons with Pendred syndrome will remain euthyroid. DFNB4 is characterized by congenital sensorineural hearing loss and dilatation of the vestibular aqueducts with the pertinent absence of thyroid changes and cochlear hypoplasia. Taken together, mutations in the SLC26A4 gene may cause up to 8%-10% of congenital deafness. The sensitivity of sequence analysis for the SLC26A4 gene is currently estimated at 50%. This testing cannot exclude the possibility of mutations in other unknown genes that cause deafness. This test should be ordered for patients with sensorineural hearing loss with temporal bone abnormalities (observed with a CT scan or MRI) and/or hearing loss associated with goiter or positive perchlorate discharge test.

Targeted SLC26A4 mutation analysis is available for family members when familial mutation is known (see Test Code: FMLIS).

 

Forms

Lab Form

CPT Code

  • 81406