Czech scientists have developed an experimental RNA-based approach that may open a new path toward treating some inherited forms of blindness. A team from the Institute of Molecular Genetics of the Czech Academy of Sciences, led by David Staněk, has shown that specially designed RNA molecules can correct a genetic defect associated with retinitis pigmentosa, a progressive retinal disease that can eventually lead to severe vision loss or blindness.
Retinitis pigmentosa usually begins quietly. Patients may first notice difficulty seeing in the dark or in dim light. Over time, the disease damages the retina, gradually narrowing the field of vision until many patients experience so-called tunnel vision. In severe cases, the condition can result in complete blindness. Although it is considered a rare disease, it has a profound impact on everyday life, limiting independence, education, work and mobility.
The Czech team focused on the PRPF31 gene, one of the important genetic causes of autosomal dominant retinitis pigmentosa. This gene carries instructions for producing a protein involved in RNA splicing, a crucial process in which cells edit RNA before using it to make proteins. When this process goes wrong, the cell may produce faulty instructions or too little of a functional protein. Retinal cells appear to be particularly vulnerable to such disruptions, although scientists still do not fully understand why.
In the new study, researchers identified a previously unknown mutation in the PRPF31 gene in a family affected by retinitis pigmentosa. The mutation was unusual because it was located not in the protein-coding part of the gene, but in an intronic region — a section normally removed during RNA splicing. In theory, such a mutation might be expected to have little effect. In practice, however, it created a false signal that confused the cell’s splicing machinery, causing RNA to be processed incorrectly and reducing production of the functional PRPF31 protein.
To study the defect, the scientists created patient-derived induced pluripotent stem cells and guided them to become retinal pigment epithelium cells. This laboratory model allowed them to observe how the mutation disrupted RNA processing in retinal cells and to test whether the error could be corrected.
The key step was the use of antisense oligonucleotides — short synthetic RNA-like molecules designed to bind to cellular RNA and influence how it is processed. In simple terms, these molecules helped the cell ignore the false signal created by the mutation. One candidate molecule successfully rescued PRPF31 RNA splicing and increased the amount of PRPF31 protein in patient-derived retinal cells.
The result is not yet a treatment for patients. The study, published in Molecular Therapy, provides a proof of principle: it shows that a precise molecular defect causing retinitis pigmentosa can be identified and at least partially corrected in a cellular model. Before such an approach could reach clinics, it would need to undergo further testing in more advanced preclinical models to assess safety, effectiveness and delivery to retinal tissue.
Even so, the research is important for two reasons. First, it highlights the role of non-coding regions of genes, which are often overlooked in genetic diagnosis but can still cause serious disease. Second, it demonstrates the potential of targeted RNA therapies in inherited retinal disorders. The eye is considered a promising target for such treatments because drugs can be delivered locally, limiting their spread to the rest of the body.
The findings also show why basic molecular research matters for future medicine. Understanding exactly how a mutation disrupts RNA processing can make it possible to design therapies aimed at the root cause of disease rather than only managing symptoms. For patients with retinitis pigmentosa and similar genetic disorders, such personalised approaches may one day offer hope where current treatment options remain limited.
