Specimen:

Whole Blood

Collection Medium:

Minimum:

Preferred Minimum:  8 mL whole blood
Absolute Minimum:  4 mL whole blood

Analytic Time:

3 months

Reference Range:

None detected

Interpretive Data:

DFNB9
The gene OTOF causes autosomal recessive nonsyndromic hearing loss at 
the DFNB9 locus, which maps to chromosome 2p23-p22.

OTOF
OTOF is a gene of 48 exons that encodes a transmembrane protein of 1230 
amino acids called otoferlin.  Otoferlin is expressed in multiple cell 
types within the cochlea.  More than 24 mutations in OTOF have been 
reported and are associated with autosomal recessive nonsyndromic 
sensorineural hearing loss.  Often, otoacoustic emissions (OAEs) are 
present while pure tone audiometry or auditory brain stem responses 
(ABRs) are grossly abnormal, features characteristic of auditory 
neuropathy.

Sensitivity is greater than 98%.

Comments:

Please print, complete and submit the Deafness Testing Requisition 
from the Molecular Otolaryngology & Renal Research Laboratory, to 
Specimen Control/Mailouts with the specimen and the Epic Requisition.

Methodology:

Screening for OTOF is performed by DHPLC and sequencing.  
Oligonucleotide primers have been designed to amplify each exon.  
Amplified samples are run on the DHPLC; abnormal elution profiles are 
sequenced to determine the specific mutation.  Exons carrying known 
SNPs are directly sequenced.

CPT Code:

83891, 83894, 83898 (x38), 83903 (x8), 83904 (x48), 83912