Hearing Loss, Nonsyndromic, Connexin 30 (GJB6) 2 Deletions

Casandra

Casandra Test Code AR42834Version 1 (DRAFT)

Performing Lab

Lab ARUP LaboratoriesLab Test ID 2001956CPT Code 81254

Hearing Loss, Nonsyndromic, Connexin 30 (GJB6) 2 Deletions

Also known as: GJB6 DEL

Clinical Use

Order Test

Use

This test is used as a diagnostic tool for individuals with nonsyndromic hearing loss and one identified GJB2 variant. It is also suitable for carrier screening when there is a family history of GJB6 deletion or for reproductive partners of individuals with GJB6 or GJB2 variants. The presence of large deletions in the GJB6 gene can lead to moderate-to-profound nonsyndromic hearing loss (NSHL). These deletions disrupt cis-regulatory elements for GJB2, impacting the expression of GJB2 and leading to compound heterozygosity that results in NSHL.

Special Instructions

Informed consent for genetic testing is required for patients in New York. A patient history form for hearing loss testing should be submitted with the order. The test sample should be transported refrigerated and may also be accepted at room temperature within stability limits.

Limitations

The test identifies two specific GJB6 deletions (309kb and 232kb). It does not detect other GJB6 variants, the etiology of hearing loss from other genetic or environmental causes, or sequence variants in other genes. Genetic errors may occur due to rare sequence variations. Interpretation of results can be impacted if the patient has undergone allogeneic stem cell transplantation. The test has not been cleared or approved by the FDA but is performed in a CLIA-certified lab.

Test Details

New York Approved