STRC-Related Disorders: STRC Deletion/Duplication MLPA

Turnaround Time

2 weeks

CPT Code(s)

81479

Cost

$500

Genes

• STRC-Related Disorders

Pathogenic variants in STRC are associated with type 16 autosomal recessive deafness (DFNB16), a nonsyndromic hearing loss, with prelingual onset. DFNB16 is caused by homozygous or compound heterozygous mutations, multi-exon or complete STRC deletions, or gene conversion between the STRC gene and the STRC pseudogene (STRCP1).

Molecular testing is useful to confirm the diagnosis and to identify the disease causing mutations within a family to allow for carrier testing and prenatal diagnosis.

multiplex ligation-dependent probe amplification (MLPA)

Alterations in the stereocilin (STRC) gene are the most common genetic etiology in patients with mild to moderate hearing loss, accounting for roughly 30% of patients in this group, and 16% among all patients with hearing loss. Most variants were large copy number variants (CNVs).

The preferred sample type is 3-5 ml of peripheral blood collected in an EDTA (purple top) tube. Extracted DNA and saliva are also accepted for this test. Saliva samples must be submitted in an approved saliva kit. Contact the lab to receive a saliva kit or to have one sent to your patient.

The specimen should be kept at room temperature and delivered via overnight shipping. If shipment is delayed by one or two days, the specimen should be refrigerated and shipped at room temperature. Do not freeze the specimen. Samples collected on Friday can be safely designated for Monday delivery.