OTOF and Hearing impairment: Autosomal recessive auditory neuropathy has been reported in association with mitochondrial myopathy and mitochondrial DNA multiple deletions [5], but commonly it presents as congenital nonsyndromic hearing impairment as a consequence of mutations in the otoferlin (OTOF) gene, a membrane-anchored calcium-binding protein that plays a role in the exocytosis of synaptic vesicles at the auditory inner hair cell ribbon synapses [6].