title: The genetic basis of auditory neuropathy spectrum disorder (ANSD).
abstract: OBJECTIVE
  Auditory neuropathy is a hearing disorder where outer hair cell function within the cochlea is normal, but inner hair cell and/or the auditory nerve function is disrupted. It is a heterogeneous disorder which can have either congenital or acquired causes. Furthermore, the aetiology of auditory neuropathy is vast, which may include prematurity, hyperbilirubinaemia, anoxia, hypoxia, congenital brain anomalies, ototoxic drug exposure, and genetic factors. It is estimated that approximately 40% of cases have an underlying genetic basis, which can be inherited in both syndromic and non syndromic conditions. This review paper provides an overview of the genetic conditions associated with auditory neuropathy spectrum disorders (ANSDs) and highlights some of the defective genes that have been found to be linked to the pathological auditory changes.
  
  
  METHODS
  Literature search was conducted using a number of resources including textbooks, professional journals and the relevant websites.
  
  
  RESULTS
  The largest proportion of auditory neuropathy spectrum disorders (ANSDs) is due to genetic factors which can be syndromic, non-syndromic or mitochondrial related. The inheritance pattern can include all the four main types of inheritances such as autosomal dominant, autosomal recessive, X-linked and mitochondrial.
  
  
  CONCLUSIONS
  This paper has provided an overview of mutation with some of the genes and/or loci discovered to be the cause for auditory neuropathy spectrum disorders (ANSDs). It has been noted that different gene mutations may trigger different pathological changes in patients with this disorder. These discoveries have provided us with vital information as to the sites of pathology in auditory neuropathy spectrum disorders (ANSDs), and the results highlight the heterogeneity of the disorder.
authors.affiliation: Long Term & Chronic Conditions Centre, College of Human & Health Sciences, Swansea University, United Kingdom. V.K.C.Manchaiah@swansea.ac.uk
authors.forename: Vinaya K C
authors.initials: VK
authors.lastname: Manchaiah
authors.forename: Fei
authors.initials: F
authors.lastname: Zhao
authors.forename: Ali A
authors.initials: AA
authors.lastname: Danesh
authors.forename: Rachel
authors.initials: R
authors.lastname: Duprey
mesh_terms: D001304:Auditory Diseases, Central / Q000175:diagnosis / Q000235:genetics; D001309:Auditory Threshold; D002648:Child; D003056:Cochlear Nerve / Q000473:pathology*; D005072:Evoked Potentials, Auditory; D016057:Evoked Potentials, Auditory, Brain Stem / Q000502:physiology; D005260:Female; D020022:Genetic Predisposition to Disease; D006319:Hearing Loss, Sensorineural / Q000175:diagnosis / Q000235:genetics*; D006801:Humans; D008297:Male; D009154:Mutation; D000160:Vestibulocochlear Nerve Diseases / Q000175:diagnosis / Q000235:genetics*