DEPARTMENT OF HEARING IMPLANT SCIENCES
SHINSHU UNIVERSITY SCHOOL OF MEDICINE
ABOUT RESEARCH SUBJECTS IN THE DEPARTMENT OF HEARING IMPLANT SCIENCES
Genetic Analysis of Deafness
Hearing loss is one of the most common sensory disorders, with more than 120 distinct genes reported as causative for non-syndromic hearing loss. Recent advances in next-generation sequencing (NGS) have provided a powerful new strategy and revolutionized the elucidation of genetic defects.
We have already performed NGS analysis for over 14,000 hearing loss patients. The most remarkable result obtained in this comprehensive study was that the obtained data could be used for the first time to clarify the genetic epidemiology from congenital/early-onset deafness to late-onset HL using the same NGS platform and the same filtering algorithm.
Hearing Implants
Cochlear implantation, which involves the insertion of the electrode into the cochlea and direct electrical stimulation of the auditory nerve, is currently the standard therapeutic option for severe-to-profound sensorineural hearing loss patients worldwide. The use of hearing implants including cochlear implants and middle ear implants is growing rapidly due to the associated benefits in terms of improved hearing. Development of new devices supported by basic research as well as clinical research is essential for further progress in this field. We are undertaking several basic research and clinical research programs on Hearing Implants and related scientific fields including the genetic background of CI patients and their auditory performance.
Bioinformatics
Recent advances in next-generation sequencing have given rise to new challenges due to difficulties in variant pathogenicity interpretation and large dataset management, including many kinds of public population databases as well as public and commercial disease-specific databases.
To solve this problem, we developed original database software, the “Clinical NGS database,” for improving clinical next-generation sequencing workflow through the unified management of variant and clinical information.
We also developed copy number analysis software for the Ion AmpliSeq platform.
Gene Expression Analysis
Despite advances in genetic analysis, there remains a significant delay in the elucidation of the pathophysiology of the auditory and vestibular systems as the inner ear is surrounded by bone, making it impossible to perform biopsies without causing irreversible deafness or valance defects.
To overcome this difficulty, we are currently performing gene expression analysis to reveal the gene expression profile of the mouse and human inner ear. As part of this study, we are using RNA-Seq analysis (short-read and long-read sequencing) to reveal spatio-temporal gene expression dynamics.
Epidemiology
About 30% of the hereditary hearing loss patients suffer syndromic hearing loss with various associated symptoms. However, most of these disorders are rare and only limited clinical information is available.
In Japan, nationwide epidemiological surveys of various hearing disorders, including juvenile onset hearing loss, Usher syndrome, BOR syndrome, delayed endolymphatic hydrops, and Waardenburg syndrome, have been conducted by the Research Group of the Ministry of Health and Welfare for Intractable Diseases.