Bilateral Nonsyndromic Sensorineural Hearing Loss Caused by a NARS2 Mutation.

Mitochondrial diseases disrupt the process of energy generation by the mitochondria, leading to manifestations that can affect almost any organ in the body. Although various possible clinical phenotypes can result, neurological and neuromuscular affection is most frequently encountered. NARS2 encodes an enzyme responsible for the conjugation of asparagine to its cognate mitochondrial transfer ribonucleic acid (tRNA) molecule, representing an essential step necessary for effective mitochondrial protein synthesis.