TECTA-Alpha Tectorin Protein (Deafness Genetic Test)
Order Code: TECTA
Epic Lab Code: LAB7331
Order Form: A-1a Miscellaneous Request or Epic Req
Commercial Mail-out Laboratory
6240 RCP
356-3527
Specimen:
Whole Blood
Collection Medium:
and
Pink top tube Pink top tube
Alternate Collection Media:
Lavender top tube 4 mL (EDTA)
Minimum:
Preferred Minimum: 8 mL whole blood Absolute Minimum: 4 mL whole blood
Analytic Time:
3 months
Reference Range:
None detected
Interpretive Data:
DFNA8/12 Linkage studies identified a region on chromosome 11q22-24 as the site of a deafness-causing gene in families segregating pre-lingual autosomal dominant nonsyndromic hearing loss that is most severe in the mid-frequencies. Audiograms displaying this type of hearing loss may be referred to as "cookie-bite" audiograms. TECTA has been identified as the causally-related gene at this locus. DFNB21 Mustapha and colleagues studied a Lebanese family with pre-lingual, severe-to-profound autosomal recessive nonsyndromic hearing loss mapping to chromosome 11q23-q25 (Mustapha et al., 1999). A splice donor mutation in TECTA was found to segregate with the hearing loss in this family. TECTA The gene, TECTA, contains 23 exons and encodes the 2155 amino acid protein TECTA (Alpha Tectorin). Alpha Tectorin is the major non-collagenous component of the tectorial membrane. In humans, mutations in TECTA cause both autosomal dominant and autosomal recessive nonsyndromic hearing loss. Over 20 mutations have been identified in TECTA including missense, nonsense, and splice site mutations. 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 TECTA is performed via 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.
CPT Code:
83891, 83894, 83898 (x23), 83903 (x13), 83904 (x10)