Crucial Roles of the m.1555A>G Mutation on MT-RNR1 Gene in Hearing Loss

Hearing loss is caused by a variety of genetic and environmental factors, with inherited causes assumed to account for 50% to 60%. Mutations in mitochondrial DNA (mtDNA) 12S rRNA, especially the m.1555A>G mutation, are the most common molecular cause for nonsyndromic sensorineural hearing loss and aminoglycoside-induced deafness. The spectra of this gene varies among different ethnic populations. In current review, the m.1555A>G mutation of 12S rRNA decoding gene was compared in different populations for ethnic-specific allele frequency and their contribution to genetic hearing loss. Differences in the distribution of mutation to diverse regions of the world showed that it occurred from the ancestors of each ancestral generation and in immigrant populations at different time periods. Furthermore, we also include the functional studies of this mtDNA variation in the etiologies of aminoglycoside-induced hearing loss. Carriers of the mutation (m.1555A>G) should avoid aminoglycosides and use alternatives for antibiotic therapy to avoid the possibility of drug-induced hearing loss. Comprehensive summary of the m.1555A>G mutation can help provide scientific basis for disease diagnosis and consultation for hearing loss and develop optimal therapeutic strategies for deaf patients.

Automated summary

Hearing loss is caused by a combination of genetic and environmental factors, with genetic factors accounting for 50% to 60% of cases. Mutations in mitochondrial DNA 12S rRNA, particularly the m.1555A>G mutation, are the most common molecular cause of nonsyndromic sensorineural hearing loss and aminoglycoside-induced deafness. The frequency of this mutation varies among different populations, possibly due to genetic differences among ancestors.