Complete List of Aminoglycoside-Induced Hearing Loss Panel Genes

MT-RNR1

MORL Screening Methodology

Targeted Sanger sequencing of MT-RNR1 variants: m.1095T>C, m.1494C>T, and m.1555A>G

(SEND ONLY ONE OF THE FOLLOWING SAMPLE TYPES) : 

  • 5µg DNA suspended in ≥ 50µl elution buffer
    • minimum concentration 50ng/µl
    • A260/A280 1.8-2.0
  • 3-5 cc EDTA Whole Blood
    • room temperature
  • Saliva
    • DNA Genotek, ORAGene Discover, OGR-500
  • Buccal Swabs 
    • at least 4 swabs
    • DNA Genotek, OraCollect, OCD-100

Click here to print sample and shipping requirements.

  • Whole Blood Sample Stability for DNA extraction
    • EDTA Whole Blood is stable for 7 days at room temperature and 4 months in the refrigerator
  • Saliva Collection Kits and Buccal Swabs Sample Stability
    • Per the manufacturer for samples collected following the instructions provided with kit/swabs: OGR-500 saliva collection kits are stable at room temperature for several years and OCD-100 buccal swabs stable up to 80 days.  Both of these kits can be shipped at room temperature.

  • Labeled with the sample type AND patient’s name, DOB, MRN and sex
  • Room temperature (DO NOT FREEZE)
  • Samples may be refrigerated if delivery is delayed
  • Shipping and receiving dock closed on weekends and holidays 
    • Deliveries accepted Monday - Friday 

Provide a pedigree, audiograms, clinic notes regarding hearing loss and temporal bone imaging studies (if performed).

 

Click here to print sample and shipping requirements.

Information

Quick Facts

  • CPT codes: 81401 
  • Test code: MTRNR1
  • Turnaround time: 3 weeks
  • Cost: $185
Requisition Form

To order:

Use this requisition form to order this test.

Background Information

  • The Aminoglycoside-Induced Hearing Loss Panel (MT-RNR1 gene) include the 3 high risk variants in MT-RNR1 associated with aminoglycoside induced hearing loss according to the Clinical Pharmacogenetics Implementation Consortium (CPIC) (m.1095T>C, m.1494C>T, and m.1555A>G). 

  • Aminoglycosides are widely used antibiotics known to have side effects including a risk of hearing loss. Individuals carrying one of three high risk variants in MT-RNR1 have an increased risk of aminoglycoside-induced hearing loss. 

  • CPIC guideline recommends individuals with the high-risk MT-RNR1 variants should “avoid aminoglycosides unless the high risk of permanent hearing loss is outweighed by the severity of infection and safe or effective alternative therapies are not available”. 

  • The MT-RNR1 gene, including the above risk variants, is also included in our OtoSCOPE v9 panel. 

  • Casano, R. A. et al.: Hearing loss due to the mitochondrial A1555G mutation in Italian families. Am J Med Genet. 79(5):388-91, 1998. PubMed ID: 9779807
  • Zhao, H. et al: Maternally inherited aminoglycoside-induced and nonsyndromic deafness is associated with the novel C1494T mutation in the mitochondrial 12S rRNA gene in a large Chinese family. Am. J. Hum. Genet. 74: 139-152, 2004. PubMed ID: 14681830
  • McDermott JH, Wolf J, Hoshitsuki K, Huddart R, Caudle KE, Whirl-Carrillo M, Steyger PS, Smith RJH, Cody N, Rodriguez-Antona C, Klein TE, Newman WG. Clinical Pharmacogenetics Implementation Consortium Guideline for the Use of Aminoglycosides Based on MT-RNR1 Genotype. Clin Pharmacol Ther. 2022 Feb;111(2):366-372. doi: 10.1002/cpt.2309. Epub 2021 Jun 20. PMID: 34032273; PMCID: PMC8613315.

The Clinical Diagnostics Service of the Molecular Otolaryngology and Renal Research Laboratories is a Joint Commission-approved CLIA-accredited diagnostic laboratory