Diagnostic testing or carrier screening for GJB2-related nonsyndromic hearing loss (NHSL). May be used as first-tier genetic test for individuals with NSHL.
Polymerase Chain Reaction/Sequencing
Lavender (EDTA), pink (K2EDTA), or yellow (ACD Solution A or B).
Transport 3 mL whole blood. (Min: 1 mL)
Ambient: 72 hours; Refrigerated: 1 week; Frozen: Unacceptable
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.
This test was developed and its performance characteristics determined by ARUP Laboratories. It has not been cleared or approved by the US Food and Drug Administration. This test was performed in a CLIA certified laboratory and is intended for clinical purposes.
Counseling and informed consent are recommended for genetic testing. Consent forms are available online.
Laboratory Developed Test (LDT)
|Component Test Code*||Component Chart Name||LOINC|
|0051375||Connexin 26, Full Gene Sequencing||35300-3|
- Connexin 26 hearing loss
- GJB2 hearing loss
- Hearing Loss, Nonsyndromic