A groundbreaking gene therapy has given four toddlers, who were born with one of the most severe forms of childhood blindness, a remarkable improvement in their vision. The experimental treatment, conducted at Moorfields Eye Hospital in London, has allowed these children to gain sight that was once thought to be unattainable. Before the therapy, they were registered as legally blind, capable only of distinguishing between light and darkness. Following the treatment, their parents reported significant progress, with some children now beginning to draw and write an outcome described as life-changing.
The study, published in The Lancet medical journal, highlights the potential of early intervention using gene therapy to address severe visual impairments caused by genetic mutations. The condition affecting these children, a rare form of Leber Congenital Amaurosis (LCA), is caused by a mutation in the AIPL1 gene, which leads to rapid degeneration of retinal cells. This results in profound vision loss from infancy, with no previously available treatment. However, researchers and doctors at Moorfields Eye Hospital, alongside specialists from University College London and Great Ormond Street Hospital, developed an innovative procedure that delivers healthy copies of the gene into the back of the eye, targeting the root cause of the disease.
One of the children who underwent the treatment is Jace, a toddler from Connecticut, USA. His parents first noticed something was amiss when, at around eight weeks old, he failed to make eye contact or respond visually in the way typical infants do. After months of medical visits and testing, they received the devastating diagnosis that their son had a rare and untreatable genetic condition. The family’s breakthrough came when they learned about the experimental gene therapy trial in London, giving them a glimmer of hope.
Jace underwent the procedure when he was just two years old. The treatment involved injecting healthy copies of the AIPL1 gene into his retina through minimally invasive surgery. These healthy genes, delivered using a harmless virus, replaced the faulty ones and triggered a process that helped the cells at the back of his eye function and survive longer.
His parents were amazed by the results. Just weeks after the procedure, they noticed subtle but significant changes in his vision. For the first time, Jace squinted in response to bright sunlight—a reaction that had never occurred before. Over time, his ability to track objects improved, and he started picking up toys and navigating his surroundings with greater ease. His father described the transformation as “pretty amazing,” emphasizing that his son was now able to engage with the world in a way that was previously impossible.
The trial included four children from the United States, Turkey, and Tunisia, all of whom showed positive responses to the therapy. Because this was a pioneering procedure, the children were treated under a special compassionate-use license, given that no alternative treatments were available. To mitigate risks, doctors treated only one eye in each child, carefully monitoring their progress over several years. Vision in the untreated eye continued to decline, reinforcing the belief that the therapy had a genuine impact.
Professor James Bainbridge, a leading retinal surgeon at Moorfields Eye Hospital, emphasized the significance of treating young children at such an early stage. He explained that severe vision impairment in infancy has devastating effects on a child’s development and ability to interact with others. By intervening early, the therapy has the potential to dramatically change their lives, giving them opportunities for learning, independence, and social engagement.
Consultant eye surgeon Professor Michel Michaelides echoed this optimism, calling the results “hugely impressive” and highlighting the transformative power of gene therapy. The medical team plans to monitor the children over the long term to assess the durability of the treatment. They are also hopeful that similar gene therapy approaches could be developed for other childhood genetic eye conditions, offering new hope to families facing similar diagnoses.
This success represents a major step forward in the treatment of inherited blindness, demonstrating that early genetic intervention can restore sight and fundamentally improve the quality of life for affected children. With continued research and advancements, gene therapy could revolutionize the treatment of genetic eye diseases, bringing light to those who were once destined to live in darkness.
