Xue Zhong Liu, MD, PhD, and research partner Zheng-Yi Chen, PhD, will investigate gene editing and CRISPR/Cas9 systems to potentially treat Usher syndrome.
The National Institute on Deafness and Other Communication Disorders (NIDCD), of the National Institutes of Health, has granted $3.5 million to Xue Zhong Liu, MD, PhD, from University of Miami Miller School of Medicine to develop a gene therapy to treat hearing loss-related Usher syndrome.
“Today’s treatment for Usher syndrome is limited to cochlear implants or hearing aids, which help to address the hearing loss, but there is no biological treatment for HL and the blindness. There is an unmet need to develop alternative treatment options,” Liu said in a statement.1 “The Miller School is one of a select few sites in the world conducting research to apply CRISPR/Cas9 gene editing for HL including Usher syndrome.”
The money will be awarded over 5 years to Liu, who serves as the Marian and Walter Hotchkiss Endowed Chair in Otolaryngology at the University of Miami Miller School of Medicine. He is also vice chair of the Department of Otolaryngology and professor of otolaryngology, human genetics, biochemistry, and pediatrics at the Miller School.
“We will use CRISPR/Cas9 to correct mutations in three different Usher genes shown in our preliminary data to cause most inherited hearing loss in USH,” Liu added.1 “This will involve strategies to rescue hearing in transgenic USH mouse models and developing CRISPR/Cas9 editing strategies to disrupt USH mutations, using human inner ear organoids derived from patient-induced pluripotent stem cells.”
Liu will investigate and develop novel gene therapy approaches for the disease, including gene editing with CRISPR/Cas9, with his collaborator Zheng-Yi Chen, PhD, Massachusetts Eye and Ear Infirmary, Department of Otolaryngology, Harvard Medical School.
“Recent breakthroughs in genetic screening, gene- or cell-based therapeutics, and gene editing for the inner ear can lead to novel therapies for multiple classes of hereditary hearing loss. We are excited as this is the first gene therapy NIH grant using CRISPR/Cas9 at UM for common sensory disorders,” Fred Telischi, MD, MEE, chair of otolaryngology, professor of neurological surgery and biomedical engineering, and James R. Chandler Chair in Otolaryngology, added to the statement.1
Liu and Chen hope that the grant and study will yield a feasible treatment for Usher syndrome based on genetic mutations. While their efforts at the Miller School are ongoing, Liu has also developed a collaborating program with the University of Miami Ear Institute and Bascom Palmer Eye Institute that aims to provide better care for people with Usher syndrome. The University of Miami Ear Institute also offers a Genetic Hearing Loss Clinic that provides testing, counseling, and intervention options to patients and families dealing with different types of hearing loss.
“This grant was awarded by the NIDCD as part of its high-impact program to help meet an unmet patient need,” Liu added.1 “Our aim is to lay the foundation for moving genome editing approaches closer to clinical trials on humans with Usher syndrome, which accounts for about 50% of all hereditary deaf-blindness cases, including in children.”
Other recent otology news out of the Miller School includes the publication of a study in Proceedings of the National Academy of Sciences in June 2022 that identified inherited mutations in the MINAR2 gene that caused deafness in 4 families.2 These genes may serve as future targets for gene therapy research.
“MINAR2 plays a major role in hearing, and these inherited mutations lead to sensorineural deafness,” senior author Mustafa Tekin, MD, professor, Dr. John T. Macdonald Foundation Department of Human Genetics, said in a statement at that time.2 “The findings suggest these cases may be suitable for intervention with genetic therapies.”