Hearing Loss, Nonsyndromic, Connexin 26 (GJB2) 35delG Mutation
0051383
 
Ordering Recommendation
Diagnostic testing for GJB2-related nonsyndromic hearing loss. Carrier screening for GJB2-related nonsyndromic hearing loss.
Mnemonic
CX 35DELG
Methodology
Nucleic Acid Probe/Fluorescence Signal Amplification
Performed
Wed
Reported
Within 14 days
New York DOH Approval Status
Specimens from New York clients will be sent out to a New York DOH approved laboratory.
Specimen Required
Patient Preparation
 
Collect
Lavender (EDTA), pink (K2EDTA), or yellow (ACD Solution A or B).  
Specimen Preparation
Transport 3 mL whole blood. (Min: 1 mL)  
Storage/Transport Temperature
Refrigerated.  
Unacceptable Conditions
 
Remarks
 
Stability
Ambient: 24 hours; Refrigerated: 1 week; Frozen: Unacceptable  
Reference Interval
By report
Interpretive Data
Background Information for Hearing Loss, Connexin 26 (GJB2) 35delG Mutation:
Characteristics:
Nonsyndromic hearing loss; paired recessive mutations typically cause congenital deafness while dominant mutations have variable expressivity.
Incidence:
Approximately 1 in 6500.
Inheritance:
Autosomal recessive or dominant depending on specific GJB2 mutation; the 35delG mutation is autosomal recessive.
Cause:
Deleterious GJB2 gene mutations; 35delG is the most common mutation in Caucasians.
Clinical Sensitivity:
80 percent of GJB2 mutations in Caucasians; less in other ethnicities.
Methodology:
Invader assay targets the GJB2 35delG mutation using a sequence specific probe and fluorescent resonance energy transfer (FRET) for signal amplification.
Analytical Sensitivity and Specificity:
99 percent.
Limitations:
Diagnostic errors can occur due to rare sequence variations. GJB2 mutations, other than 35delG, will not be detected. Mutations in other genes causing nonsyndromic hearing loss will not be detected.



Counseling and informed consent are recommended for genetic testing. Consent forms are available online at www.aruplab.com.

See Compliance Statement C: www.aruplab.com/CS
Note
ARUP Medical Director or Genetic Counselor approval is required prior to testing. Before ordering, contact a Genetic Counselor at (800)242-2787, extension 2141.
CPT Code(s)
81253
Components
Component Test Code*Component Chart Name
0051383Connexin 26 (GJB2), 35delG Mutation
2001303CX 35DELG Specimen
* Component test codes cannot be used to order tests. The information provided here is not sufficient for interface builds; for a complete test mix, contact interface support at interface.support@aruplab.com.
Cross References