PTPRQ (protein tyrosine phosphatase receptor type Q) is a transmembrane receptor essential for inner ear mechanosensation and hearing. Functionally, PTPRQ localizes to the stereociliary base and apical plasma membrane of inner ear hair cells, where it plays a critical role in stereocilia structure and function 12. PTPRQ interacts with cytoplasmic proteins TPRN and CLIC5 to form concentric rings at the stereocilia taper region, stabilizing the F-actin core and connecting it to the plasma membrane 12. This architecture enables optimal pivot-point flexibility for sound-induced deflections and sustained mechanosensitivity 2. Disease-wise, PTPRQ mutations cause autosomal recessive non-syndromic hearing loss (DFNB84) and postlingual progressive sensorineural/mixed hearing loss with vestibular dysfunction 34. Additionally, ultrarare heterozygous PTPRQ variants contribute to age-related hearing loss (presbycusis) in 8.9% of severe cases versus <1% of controls, indicating haploinsufficiency effects 5. Clinically, PTPRQ gene variants represent targets for emerging inner ear gene therapy approaches, particularly for monogenic forms of hearing loss and presbycusis where restoration of normal protein levels can rescue auditory function 51.