Historical Aspects of Gene Therapy and Stem Cell Therapy in the Treatment of Hearing and Balance Disorder

ABSTRACT This review presents many but not all the major historical events that have led to our current understanding of gene and stem cell therapies for the treatment of hearing and balance disorders in animal models of these disorders. In order to better understand the application of these emerging therapies to the treatment of inner ear disorders in a clinical setting, it has been necessary to provide some genetic and pathobiology backgrounds from both animal models and clinical disorders. The current focus and goal of gene and stem cell therapies are directed toward understanding the effective treatment of animal models that mimic human disorders of hearing and balance. This approach not only addresses the most effective ways to deliver the gene or stem cell therapies to affected inner ears, it also provides an assessment of the efficacy of the applied therapy(s) in achieving either partial or full restoration of either hearing and/or balance within the animal models receiving these therapeutic interventions. This review also attempts to present a realistic assessment of how close the research fields of gene and stem cell therapies are to application for the treatment of human disorders in a clinical setting. Progress made in developing these novel therapies toward clinical applications would not have been possible without the many pioneering studies and discoveries achieved by the investigators cited in this review. There were also many other excellent studies performed by gifted investigators that were not able to be included within this review. Anat Rec, 303:390–407, 2020. © 2019 American Association for Anatomy