Test Directory

Confirms a diagnosis of GJB2-related nonsyndromic sensioneural hearing loss and detects carriers. This test detects mutations in the coding region and noncoding first exon of the (GJB2) gene, plus at least two and typically 20 flanking intronic nucleotides upstream and downstream of each coding exon, covering the conserved donor and acceptor splice sites.

Specimen Type: Whole Blood

Collection Container: Pale Yellow Top (ACD)

Alternate Collection Container: Lavender Top (EDTA)

Desired Specimen Volume: 7 mL

1. Collect a pale-yellow top (ACD) tube via venipuncture.

1. Transport 7 mL of whole blood in the original collection container.

Transport to the laboratory refrigerated.

See patient report.

This method does not reliably detect mosaic variants; large deletions; large duplications, inversions, or other rearrangements; deep intronic variants or variants outside of the regions targeted by this analysis. It may be affected by allele-dropout, it may not allow determination of the exact numbers of T/A or microsatellite repeats, and it does not allow any conclusion as to whether two heterozygous variants are present on the same or on different chromosome copies.

• Connexin 26
• Hearing Loss (GJB2)
• GJB2 Sequencing, Full Gene Sequencing