title: Clinical characterization of a novel COCH mutation G87V in a Chinese DFNA9 family.
abstract: OBJECTIVE
  To characterize the clinical features of a Chinese DFNA9 family associated with a novel COCH mutation and to confirm the proposed genotype-phenotype correlation of COCH.
  
  
  METHODS
  Mutation screening of 79 deafness genes was performed in the proband by targeted next-generation sequencing. Co-segregation of the disease phenotype and the detected variants was confirmed in all family members by PCR amplification and Sanger sequencing. The progression of hearing impairment in affected family members was followed and the concomitant vestibular dysfunction was verified by the caloric vestibulo-ocular reflex test.
  
  
  RESULTS
  A novel COCH mutation p.G87V was identified in the family segregating with late-onset, progressive sensorineural hearing impairment and consistent vestibular dysfunction.
  
  
  CONCLUSIONS
  The p.G87V mutation leads to a very similar phenotype as a previously reported p.G87W mutation of COCH. Our study suggested that the G87 residue is critical for function of COCH and further confirms a previously proposed genotype-phenotype correlation for DFNA9.
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai 200092, China; Ear Institute, Shanghai Jiaotong University, Shanghai 200092, China.
authors.forename: Dong-Ye
authors.initials: DY
authors.lastname: Chen
authors.forename: Yong-Chuan
authors.initials: YC
authors.lastname: Chai
authors.forename: Tao
authors.initials: T
authors.lastname: Yang
authors.forename: Hao
authors.initials: H
authors.lastname: Wu
mesh_terms: D044466:Asian People / Q000235:genetics*; D001301:Audiometry, Pure-Tone; D004252:DNA Mutational Analysis; D016326:Extracellular Matrix Proteins / Q000235:genetics*; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006319:Hearing Loss, Sensorineural / Q000175:diagnosis / Q000235:genetics*; D006801:Humans; D008297:Male; D020125:Mutation, Missense; D010375:Pedigree; D010641:Phenotype; D016133:Polymerase Chain Reaction / Q000379:methods; D012027:Reflex, Vestibulo-Ocular / Q000235:genetics / Q000502:physiology
chemical_list: C110668:COCH protein, human; D016326:Extracellular Matrix Proteins
keywords: COCH; DFNA9; Hearing impairment; Novel mutation; Vestibular dysfunction