Overall, there were two aims of this study: (1) to investigate the distribution of the hair cell-specific marker, myosin VIIa (MYO7A), and nerve fibre marker, neurofilament H, in the vestibular neuroepithelium from patients with MD and compare it to that in normal human vestibular neuroepithelial tissue; and (2) to confirm the viability of recording functional responses of surviving hair cells from MD neuroepithelium. Here, MYO7A is linked to Menkes disease.