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
- 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).
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