Tobramycin response

Aminoglycosides are widely used antibiotics which inhibit protein synthesis in bacteria by binding to bacterial 16S ribosomal subunits. Aminoglycosides are associated with a number of adverse events, including nephrotoxicity and ototoxicity. The risk of aminoglycoside-induced ototoxicity is increased in patients who carry certain variants in the MT-RNR1 gene. MT-RNR1 is found in the mitochondrial genome and encodes the 12S ribosomal subunit. Some MT-RNR1 variants cause the 12S subunit to more closely resemble the bacterial 16S subunit, which can lead to aminoglycoside molecules binding to the ribosome. This ultimately results in hearing loss due to cell death in the cochlea. The Clinical Pharmacogenetics Implementation Consortium (CPIC) have published recommendations on aminoglycoside use in patients carrying MT-RNR1 variants in the journal Clinical Pharmacology and Therapeutics. These recommendations are also available on the CPIC and PharmGKB websites. [from PharmGKB]