Researchers are making strides in developing gene editing treatments for Usher syndrome, a rare genetic disorder characterized by hearing and vision loss. The work focuses on addressing the unmet medical need for treatments that can restore or preserve hearing and vision in affected individuals.
Understanding Usher Syndrome and Current Treatments
Usher syndrome results from mutations in genes essential for the development and function of sensory cells in the inner ear and retina. Currently, there is no cure, and management focuses on addressing hearing and vision impairments through interventions like cochlear implants, hearing aids, low vision aids, and vision rehabilitation training.
Gene Editing Strategy for Usher Syndrome Type 2A (Ush2A)
Zheng-Yi Chen, DPhil, and his team are focusing on Usher syndrome type 2A (Ush2A), the most common form of the condition. They are employing a gene-editing strategy called exon skipping to target mutations in the Ush2A gene. The Ush2A gene is too large for conventional adeno-associated virus (AAV) vector-based gene therapy. This approach aims to eliminate the mutation-carrying DNA and restore the production and function of the Ush2A protein. Preclinical studies in cultured inner ear organs and transgenic mouse models have shown promising results, with the restoration of functional inner ear sensory cells (hair cells).
Potential of Gene and Cell Therapies
Both gene therapy and cell therapy hold significant potential for treating Usher syndrome. Gene therapy has demonstrated success in restoring hearing and vision by targeting different genes. Cell therapy, such as stem cell transplant, may be more effective for the retina due to its accessibility.
Other Promising Treatments in Development
There are other exciting developments in treatments for Usher syndrome, including Ush1B, Ush 1F, and Ush2C in animal models. It is crucial to demonstrate treatment efficacy in mature animal models before moving to clinical trials, given that the human newborn inner ear is fully mature.
The Future of Usher Syndrome Treatment
The field is at an unprecedented moment where treatments for Usher syndrome can become realities in the near future. The involvement of everyone and doubling efforts to make it happen is needed. Successful gene therapies for hearing loss and vision loss offer valuable lessons for developing treatments for Usher syndrome.
