Elucidation of the cause of GER embryonic degeneration and the mechanism of onset of hearing loss in a congenital hearing loss model

2022 Fiscal Year Final Research Report

• Project/Area Number: 20K22986
• Research Category: Grant-in-Aid for Research Activity Start-up
• Allocation Type: Multi-year Fund
• Review Section: 0906:Surgery related to the biological and sensory functions and related fields
• Research Institution: Jikei University School of Medicine
• Principal Investigator: Takahashi Erisa 東京慈恵会医科大学, 医学部, 助教 (20875546)
• Project Period (FY): 2020-09-11 – 2023-03-31
• Keywords: 内耳 / GER / 難聴

Outline of Final Research Achievements

We found new phenotype which is "degeneration of the fetal greater epithelial ridge (GER)" in the inner ear using model mice of congenital hearing loss. GER is essential for inner hair cell maturation. In the transgenic mice which demonstrate previously expressed cells of the gene X responsible for congenital hearing loss with GFP labelling, we found that GFP-positive cells abnormally infiltrate the GER. In addition, we confirmed that there are no changes of cell markers of stria vascularis, hair cells, supporting cells, and neural cells.
These results may suggest that degeneration of the fetal GER cause congenital hearing loss.

Free Research Field

内耳

Academic Significance and Societal Importance of the Research Achievements

難聴は先天性疾患の中でも最も多いものの一つであり、その発症メカニズムの解明は治療戦略において重要である。本研究ではGERの胎生期変性という新しい表現型を発見した。
これらの研究成果を基盤にして、近い将来、GER胎生期変性を原因とする先天性難聴に対する治療戦略の確立を目指す。