The rs267606617 A allele (also known as the 1555A allele) is assigned as a MT-RNR1 normal risk of aminoglycoside-induced hearing loss allele by CPIC. Patients with the A allele may have a decreased, but not absent, risk of experiencing aminoglycoside-induced hearing loss as compared to patients with the G allele. MT-RNR1 is a mitochondrial gene and is inherited as a haploid (i.e. there is only ever one allele present). Other genetic and clinical factors may also influence risk of aminoglycoside-induced hearing loss.