Developing a Gene Therapy that Preserves or Restores Vision in Patients with Usher Syndrome 1B
2017 Gund Harrington Scholar
Broadly, the three types of Usher syndrome are characterized by partial or total hearing loss, as well as vision loss that worsens over time. With Type 1, individuals are born profoundly deaf, and experience progressive vision loss that begins in childhood. “This form of Ushers is especially heartbreaking, as just when the individual and their family has come to grips with their deafness, they learn that blindness is likely,” Dr. Boye says.
Usher syndrome is further subdivided into types, based on the mutated gene causing the disease. Dr. Boye's focus is on type 1B which is caused by mutations in the gene MYO7A. “The idea is to deliver a healthy copy
of MYO7A to the retina of these patients,” Dr. Boye says. “But the vector currently being used to deliver genes to patient retinas isn't big enough to accommodate a gene this large. We therefore split MYO7A in half, and deliver both halves to the retina via two different vectors. Gene halves are designed to have complementary sequences, which allows them to find each other, bind together, and form full length MYO7A.
If successful, this dual vector method would change the game for other investigators seeking to address retinal diseases associated with mutations in large genes.
“I've long been fascinated with neuroscience, and the idea that we can use gene therapy to restore someone's vision was very moving to me,” Dr. Boye says. “Nothing spoke to me more than the concept of helping a blind person to see again.”
“I want to restore/preserve people's eyesight, enabling them to most effectively navigate their way through daily life.”