EYSON

Abstract

The EYSON project aims to develop a new therapeutic strategy for a type of hereditary sight loss caused by a mutation in the EYS gene. This mutation leads to progressive vision loss. There are currently no treatments for vision loss caused by the EYS gene mutation. The knowledge and results obtained in this project aim to help improve the quality of life of these patients by maintaining their vision throughout their lives.

A new technique called ‘Prime editing’ will be used to correct a specific mutation in the EYS gene, which is very common in Portugal. This technique makes it possible to modify a DNA sequence very precisely and safely. It is different from other gene editing techniques because it is less likely to make unintended changes to the DNA. To test whether PE can fix this particular genetic mistake in the EYS gene, we will use cells from patients with inherited vision loss. In the laboratory, these cells will be turned into tridimensional (3D)-mini-retinas which we expect will recapitulate the changes observed in the patient's retinas. We will then use PE to correct the genetic mistake in these 3D-mini-retinas/cells and see if it works. We will study whether the corrected cells can show better morphology, survival or function than the cells with the genetic mistake. If the corrected cells work or survive better, this could be a promising new treatment for inherited vision loss caused by a mutation in the EYS gene.