University of Toronto researchers rush to treat rare disease affecting hearing and vision in newborns

Researchers at the University of Toronto are working on a genetic treatment for the symptoms of Usher syndrome, a rare condition that leaves newborns with profound hearing loss and gradually deprives them of their vision.

Directed by Vincent Tropépe, a professor in the Department of Cell Biology and Systems at the Faculty of Arts and Sciences, research into Usher syndrome type 1F (Usher 1F) suggests that gene therapy may be able to correct vision loss ( hearing loss can be alleviated with electronic cochlear implants).

Tropepe says the work is focused on determining how specific genetic mutations affect the shape and integrity of photoreceptors, the light-sensing cells in the retina.

“We believe that in Usher 1F, photoreceptors do not mature properly during development and shape their outer segment, the part of the cell that captures photons of light, is defective and often detaches from the rest of the cell,” he said.

“Photoreceptors naturally repair their outer segments due to ‘wear and tear’ in processing light. We believe we can correct the gene and take advantage of the eye’s natural ability to recreate photoreceptor membranes to restore their shape and even regrow their outer segments.

Tropepe and his team recently received a financial boost of $ 50,000 for their work from the Usher 1F Collaborative, a nonprofit organization based in the United States. The additional support preceded Usher Syndrome Awareness Day on September 18.

“Funding like the Collaboration Grant and also from Fighting Blindness Canada allows me to hire excellent interns so that I can begin to approach this research in multiple directions in parallel,” Tropepe said.

Scientists have identified three types of Usher syndrome based on the degree of hearing and visual loss, Usher 1F being the most severe. In the United States and Canada, about four in 100,000 newborns have Usher syndrome.

There is currently no cure.

For thousands of people born with Usher 1 who are gradually losing their sight, time is running out, says Springer sari, director of the collaborative, whose two nieces are among those affected by the disease.

One niece recently started a master’s degree at American University in Washington, DC and the other is a graduate of University College London and a former Peace Corps volunteer with a successful career in the nonprofit sector. Both are increasingly concerned about the course of their vision loss, says Springer, a University of Toronto alumnus who graduated in 1986 with a Bachelor of Arts in Sociology as a member of the University College.

Left: Rachel and Jessica Chaikof lose their sight to Usher 1F. Right: Sari Springer, Director of Usher 1F Collaborative (photos courtesy of Rachel Chaikof and Littler)

“Vince’s research is extremely important because it’s focused on gene therapy and he’s making tremendous progress. We just need to cross the finish line to save the sight of these young children and adults, ”said Springer.

“Science says that by the time they are in their 40s or 50s, they will have no vision. Vince is working lightning fast to find the cure, but with each passing day another potential day of further loss of sight.

Tropepe works with a researcher and a doctoral student Amanda miles, a former student who obtained her Honors BA in Cellular and Molecular Biology in 2014 as a member of the University College.

He hopes to add up to two post-doctoral researchers with the new collaborative funding. It is also call for more help to accelerate progress.

“Really what we need is a small team of people. When you have those kinds of resources, you can start to add to the great people we already have working on this topic, ”says Tropepe, who thinks there are several other promising research threads like drug treatments that can be found. be useful in tandem with gene therapy. .

Miles says the Usher 1F research project – only a few years old – began with a discussion between her, Tropepe, and André Émili, a former professor of molecular genetics at the University of Toronto who is now at Boston University.

“This is a great example of how the University of Toronto research community fosters collaborative discussion,” says Miles.

University of Toronto students living with a disability can count on a world-class network of support services, adds Springer, an attorney who advises the university on disability issues.

“I have worked a lot with the Accessibility Services office at the University of Toronto and they are an incredibly passionate and dedicated group of people,” says Springer.

“I come from the bottom of my heart, because of my two nieces. I understand what it means to be successful in college and how difficult it is without the help of such an accomplished Accessibility Services team.