Gene therapy rapidly improves night vision in adults with congenital blindness. Using a single adeno-associated virus vector, researchers were able to insert a corrective copy of the defective gene into the retina cells of affected individuals, resulting in nearly complete restoration of night vision. The findings, published in the journal Nature, offer new hope for the estimated 1.5 million people worldwide who suffer from a complete loss of sight due to congenital genetic defects.
The study was conducted by a team of international researchers led by Dr. Shaofeng Zhou of the Chinese Academy of Sciences. Using a viral vector carrying a functional copy of the RPE65 gene, the team injected the vector into the retinas of 7 patients with Inherited Retinal Dystrophy due to RPE65 mutations. All 7 patients showed significant improvement in their ability to see at night, with 6 of them achieving nearly complete restoration of night vision.
The RPE65 gene is responsible for producing an enzyme essential for the proper function of the retina. Mutations in this gene are known to cause Inherited Retinal Dystrophy, a degenerative disease that leads to blindness. There is currently no cure for this condition.
The findings of this study offer new hope for the millions of people worldwide who suffer from Inherited Retinal Dystrophy. The results suggest that gene therapy may be a viable treatment option for this condition, and that it has the potential to restore sight in patients who have been blind for many years.
The study was funded by the National Natural Science Foundation of China, the National Key Research and Development Program, and the Chinese Academy of Sciences.
Scientists have used gene therapy to improve night vision in people who have been blind since birth, a small new study reports.
The study, published Wednesday in the journal Nature, is the first to show that the treatment can work in adults.
Researchers injected a corrective gene into the eyes of three men, ages 23 to 33, who had a rare genetic disorder that kept them from seeing in low light.
After the treatment, the men’s night vision improved by 400 to 600 percent, the study found. They were also able to read two to three lines lower on an eye chart.
“This is a start, but there’s a lot more work to do,” said lead author Dr. Eric Silvers, a clinical professor of ophthalmology at the University of Pittsburgh School of Medicine.
The men in the study have a condition called Leber congenital amaurosis, which affects about 2,000 people in the United States.
People with the disorder are born with normal vision, but it deteriorates over time, often leaving them completely blind by adulthood.
There is no current treatment for the condition.
The new study is a small, early step toward the possible use of gene therapy to treat other forms of blindness, Silvers said.
“The findings open up a whole new avenue of research,” he said.
The next step is to test the treatment in a larger group of people with the disorder. If it is found to be safe and effective, it could be used to treat other forms of blindness caused by defects in a gene called RPE65, Silvers said.