Identification Of The Causative Genes For A Chinese Family With Autosomal Dominant Hereditary Hearing Loss And A Sporadic Case Of Usher Syndrome

Hearing loss is a serious sensory disorder affecting the quality of lives. The number of deafness has reached to 28million in China, among which more than 11 million are caused by inheritance. The causative genes identification and relevant molecular mechanism exploration play important roles in the prevention and therapy of hereditary hearing impairment. In our study, we analysed the clinical phenotype and investigated causal genes in subjects from a family with delayed dominant hereditary sensorineural deafness.Targeted region sequencing approach and whole exomes sequencing technology were applied in the process of research. Another study was mainly about the diagnosis and two novel pathogenic mutations identification of a case of Usher syndrome.Parti Analysis of clinical phenotype and identification of causative genes in a family with delayed sensorineural deafnessHN-F001 family was characterized by postlingual, progressive, bilateral, symmetric, sensorineural hearing loss along with tinnitus in different degrees. The average age of onset was 20-30 years old. High frequencies hearing loss at the earlier stage following on all frequencies sensorineural deafness gradually was observed among patients in the family. All members had no any other organ dysfunctions.The pedigree chart suggested that the mode of inheritance of this family was inferred to be autosomal dominant.By performing targeted region sequencing,whole exome sequencing and Sanger sequencing,there was not any positive locus heterogeneity exposed. The next step of our research strategy is to screen copy number variation through array-based comparative genomic hybridization.Part2 The diagnosis and two novel pathogenic mutations identification of a sporadic case of Usher syndrome.A sporadic case of congenital sensorineural deafness, an eleven years old child, was collected in the process of deafness investigation performed by our research team in Anhui province. She had an nyctalopia onset when she was 6 years old.By conducting targeted region sequencing and Sanger sequencing, the novel causative heterozygous mutations c.1959delG and c.4152G>C in MY07A gene were identified.According to the clinical and molecular genetic features, she was primary diagnosed Usher syndrome.While the thorough examinations of visual function and vestibular function are to be conducted so that we make the final diagnosis.The examination results are to be added later.