Therapeutic research begins with testing new therapies in laboratory models of the disease before moving to human trials. However, translating success from models (cells or animals) to humans is challenging because they develop function and symptoms at different rates.
Recently, a team of researchers in Paris, France, successfully developed an adeno-associated viral (AAV) gene therapy that restored inner ear function in adult USH1G mice when the treatment was given just after birth. However, since all mice are born deaf and only begin to hear around the 2nd week of life while humans develop hearing in utero around the 19th week of pregnancy, it was unknown whether treatment after birth in humans (like was done in the mouse model), would work to restore hearing. To address this gap, the team expanded the treatment window for their USH1G mice. Their investigation revealed that the gene therapy could be administered for up to nine additional days, going beyond the mouse neonatal stage, while maintaining its effectiveness. This suggests administration of this gene therapy to newborn humans with USH1G instead of in utero may be possible.
What this means for Usher syndrome: As genetic testing becomes more common in Usher diagnosis, newborns with USH1G may have the opportunity to receive a gene therapy shortly after birth, potentially leading to enhanced vestibular function and hearing.