Mutations in LOXHD1 gene can cause auditory neuropathy spectrum disorder

OBJECTIVES: The aim of this paper was to study the auditory phenotype of three related children with sensorineural hearing loss (2 sisters and their cousin) following genetic analysis revealing mutations in LOXHD1. METHODS: Genetic testing was conducted on three related children. They were assessed with a standard clinical test battery including distortion otoacoustic emissions, auditory brainstem responses and audiometry. RESULTS: We identified heterozygous variants in LOXHD1 in a family of Irish/German and Italian/Irish ancestry with autosomal recessive auditory neuropathy spectrum disorder (ANSD). Mutations in LOXHD1 (MIM #613072) have been linked to an autosomal recessive nonsyndromic hearing loss (DFNB77), mapped to the locus 18q12-q21. All three subjects had evidence of some, albeit few, functioning cochlear hair cells as revealed by the presence of a cochlear microphonic and/or partial otoacoustic emissions early in life. CONCLUSION: To our knowledge, this is the first association between LOXHD1 mutations and ANSD in two patients who have been successfully managed with cochlear implants.