On the pathophysiology of DFNA9: Effect of pathogenic variants in the COCH gene on inner ear functioning in human and transgenic mice

•Overview of the different pathogenic variants in the COCH gene and their different phenotypes.•Effect of COCH mutations on intracellular trafficking and inner ear pathology.•Differences in histopathology between human patients and DFNA9 mouse models.•The role of COCH in immune response, inflammation and infection in the spiral ligament.