Gene therapy

Genetic causes of macular disease

Many macular dystrophies, such as Stargardt disease, Best disease and Sorsby Fundus dystrophy, are due to a mutation in a single gene. These diseases are often seen to run in families; children may inherit the harmful changes in a gene from either their mother or father or from both of their parents.

The faulty gene can lead to the cells in the macula not functioning correctly, or can cause cell death, therefore leading to vision loss.

However, through gene therapy, researchers are hoping to be able to stop the effects of the mutation by fixing, removing or replacing the faulty gene with a healthy copy of the gene.

The Macular Society has funded multiple research projects looking at creating a variety of gene therapies for different macular dystrophies.

Gene therapies are also being investigated for macular dystrophies, as they are inherited conditions. If we can fix the mutation in the affected gene we could hopefully stop the condition. There are a few different ways researchers are looking into gene therapy.

One way is adding new healthy copy of the affected gene into the eye. The idea is that by adding more of the healthy gene, we are giving more instructions to make the healthy copy of the protein the gene produces and this may restore more function to the eye.

Gene editing is another technique being used. This is more complex as it involves fixing the mutation in the affected gene. This can hopefully remove the faulty mutation and restore the gene to a healthy copy and may stop the disease. However, as there are a number of different mutations in the gene that causes macular dystrophies it can be very particular and may require individualised treatments for each mutation, which can make treatment slow and expensive. We have a project looking into this area of research for Stargardt disease.

Research is also looking at other gene therapies to increase or decrease the expression of genes related to macular dystrophies. Gene expression controls how much or if any protein is produced from the gene. In some macular dystrophies the mutation in the gene causes less protein to be produced or for the protein to be less functional, so increasing gene expression can help improve the function of the macula, we are funding research into this for Stargardt and Best disease. In other macular dystrophies the mutation in the gene causes a protein to be produced which has a harmful effect on the cells of the eye, therefore stopping the expression of the gene can help keep the macular cells healthy. There is a project investigating this for Doyne Honeycomb Dystrophy.

We are currently funding research into different areas of gene therapy for macular dystrophies. You can find out more about these projects.