MT-RNR2

MT-RNR2, also known as Mitochondrial Ribosomal RNA 16S, is a human gene located in mitochondrial DNA (mtDNA). It encodes the 16S ribosomal RNA (16S rRNA), a component of the mitochondrial ribosome.

The mitochondrial ribosome, distinct from ribosomes found in the cytoplasm, is responsible for protein synthesis within the mitochondria. These proteins are essential for oxidative phosphorylation, the process by which cells generate energy in the form of ATP. The 16S rRNA provides a structural and functional scaffold for the mitochondrial ribosome, facilitating the binding of messenger RNA (mRNA) and transfer RNA (tRNA) during translation.

Mutations in the MT-RNR2 gene have been associated with a variety of human diseases, particularly those affecting hearing. The most common manifestation is non-syndromic sensorineural hearing loss (NSHL), which can range from mild to profound. Specific mutations in MT-RNR2, such as the A1555G mutation, have been identified as significant contributors to aminoglycoside-induced ototoxicity. Aminoglycosides are a class of antibiotics that can cause hearing loss as a side effect, and individuals carrying certain MT-RNR2 mutations are more susceptible to this adverse reaction.

In addition to hearing loss, variations in MT-RNR2 have been implicated in other conditions, including maternally inherited Leigh syndrome (MILS) and cardiomyopathy. These associations highlight the critical role of mitochondrial protein synthesis in cellular function and the pleiotropic effects of MT-RNR2 mutations. Genetic testing for MT-RNR2 mutations is often performed in individuals with unexplained hearing loss, especially those with a family history of the condition or a history of aminoglycoside exposure. The identification of such mutations can have important implications for diagnosis, prognosis, and genetic counseling.