Connexin 26 (GJB2), Sequencing
0051374
 
Ordering Recommendation
Diagnostic testing for GJB2-related nonsyndromic hearing loss. Carrier screening for GJB2-related nonsyndromic hearing loss.
Mnemonic
CX26SEQ
Methodology
Polymerase Chain Reaction/Sequencing
Performed
Varies
Reported
Within 21 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: 72 hours; Refrigerated: 1 week; Frozen: Unacceptable  
Reference Interval
By report
Interpretive Data
Background Information: Connexin 26 (GJB2) , Sequencing
Characteristics:
Nonsyndromic hearing loss; recessive mutations typically cause congenital deafness while dominant mutations have variable expressivity.
Incidence:
Approximately 1:6500.
Inheritance:
Autosomal recessive or dominant depending on specific GJB2 mutation.
Cause:
GJB2 gene mutations.
Clinical Sensitivity:
95 percent of GJB2 mutations.
Methodology:
Bidirectional sequencing of the entire coding region, exon/intron boundaries, and 5'-UTR of the GJB2 gene sequenced.
Analytical Sensitivity and Specificity
: Greater than 99 percent.
Limitations:
Diagnostic errors can occur due to rare sequence variations. Large GJB2 gene deletions or deep intronic mutations will not be identified; hearing loss caused by other genetic or environmental causes 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
CPT Code(s)
81252
Components
Component Test Code*Component Chart Name
0051375Connexin 26, Full Gene Sequencing
2001348CX26SEQ 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
  • Hearing Loss, Nonsyndromic