Those with Usher syndrome--the leading hereditary cause for simultaneous deafness and blindness, for which there is no treatment--may have a new reason for hope now that researchers have confirmed the first-ever nonhuman primate model of the disease. Genetic mutations lead those with Usher syndrome to be born deaf, experience balance issues, and gradually lose their sight. A treatment for Usher syndrome--which affects an estimated 4 to 17 out of every 100,000 people--has been stymied by the lack of an animal model that closely mimics how the disease affects people. An Oregon Health & Science University (OHSU) research team has been working to fill that gap. The researchers confirmed that their model--a rhesus macaque born a year ago--has symptoms that mirror the most severe form of Usher syndrome, Type 1B, and reported these findings during a February 11, 2023 podium presentation at the Association for Research in Otolaryngology 46th Annual MidWinter Meeting in Orlando, Florida. The researchers used the gene-editing technology CRISPR/Cas9 to create the model, and thereby make it possible to test experimental gene therapies for Usher syndrome. The presentation was titled “Congenital Deafness, Vestibular Dysfunction, and Progressive Visual Impairment in a Rhesus Macaque Model of Usher Syndrome Type 1B.”