Helping People Maintain Their Eyesight Is Goal of Researcher
Published August 2010
Imagine living life without the ability to hear and then slowly losing the ability to see as you grow older.
For people born with Usher syndrome, that scenario is real.
Now, a researcher at UC and Cincinnati Children’s Hospital Medical Center is studying genetic mutations behind this rare illness in an attempt to find therapies to slow or stop the onset of blindness in this population.
Zubair Ahmed, PhD, assistant professor of ophthalmology, has received a four-year, $200,000 Career Development Award from Research to Prevent Blindness (RPB) to study DNA samples of people with the disorder living in India, Pakistan and the United States and to identify the genes and mutations that cause the disease.
"People with Usher syndrome type I are born deaf and experience vision loss that first starts as tunnel vision and leads to legal blindness in adulthood,” he says, adding that it results in balance and communication problems for those it affects.
"In order for a child to have the syndrome, the parents must be carriers of the mutation; it often occurs in children whose parents are related.
"Culturally, this often happens in Indian and Pakistani populations because of marriages within the same extended family.”
Ahmed came to UC in 2009 after completing his postdoctoral fellowship with the National Institutes of Health (NIH) where he and a handful of other researchers studied the genetics behind Usher syndrome.
He says that UC and Cincinnati Children’s are known nationally for their care, and because of that, many cases of Usher syndrome are referred to the institutions.
Researchers at the University of the Punjab in Pakistan will help in collecting samples overseas.
"If one is blind, he or she can use hearing to live in society; if one is deaf, he or she can use sight,” he says.
"These patients don’t have either, making communication a truly difficult feat. However, vision in these patients is intact at some point. We hope to find why it diminishes at the rate it does and stop it from doing so, giving these patients a better chance at a normal life.”
Ahmed says researchers are already aware of about five different gene mutations that lead to Usher syndrome type I but there are many more that are unknown.
"We want to understand the natural progression of the disease to answer these questions: Why does it vary? What causes some patients to lose their vision earlier than others?” he says.
"Once we understand this, our hope is to come up with therapies and then compare them to see which are most effective to the respective mutations.”
Ahmed says the RPB grant will allow him to pursue other aspects of his work, which is part of an NIH-supported intramural project at the National Eye Institute, the National Institute on Deafness and Other Communication Disorders and Cincinnati Children’s.
Currently, Ahmed says the best treatment for Usher syndrome patients is a cochlear implant.
"This helps them at least retain hearing to some extent,” he says.
"However, someday, we hope that there will be a way to stop the vision loss, too, giving these patients a chance to see and hear the world in which they live.”