Glaucoma silently steals your vision, beginning with the gradual loss of your peripheral vision. Often, one eye compensates for the sight lost in the other. Unfortunately, you may not even realize what’s happening until irreversible damage has occurred, resulting in permanent vision loss.
Existing treatments for glaucoma primarily focus on reducing eye pressure. However, the long-awaited dream has been to strengthen the retina itself, enabling it to withstand pressure build-up and prevent the damage that leads to blindness.
Excitingly, scientists have made a groundbreaking discovery: they have identified a set of genes that can be targeted to trigger “neuro-protection” in retinal cells. Furthermore, they have identified existing drugs that can be used to target these genetic factors. This discovery paves the way for revolutionary treatments that can prevent retinal damage and the subsequent blindness caused by glaucoma.
The largest-ever global genetic study on glaucoma, led by QIMR Berghofer, has revealed hundreds of new genes associated with the risk of developing this degenerative eye disease.
The findings, published in Nature Genetics, significantly advance our understanding of glaucoma’s genetics. They build upon a previous study in 2021 that identified 185 previously unknown genes linked to glaucoma, bringing the total to an impressive 312 genes.
Glaucoma stands as the leading cause of irreversible blindness worldwide, affecting over 75 million individuals, including 300,000 Australians. This disease occurs when fluid pressure in the eye increases, causing damage to the retina and the optic nerve.
Alarmingly, around 50% of glaucoma cases go undiagnosed until irreversible optic nerve damage has already taken place. Hence, early diagnosis and treatment play a critical role in mitigating its effects.
Professor Stuart MacGregor, an internationally recognized genetic epidemiologist heading QIMR Berghofer’s Statistical Genetics Laboratory and lead researcher of this study, emphasized the urgency for a new approach to treatment.
“Our findings are really exciting because for the first time we’ve discovered the set of genes that could be targeted to induce this ‘neuro-protection’ in the retinal cells.
“We’ve also identified existing drugs that could be used on those genetic targets. This could rapidly advance effective treatment to finally prevent retina and optic nerve damage.”
Repurposing existing drugs offers numerous advantages, including faster translation of research findings into patient treatments, as the safety of these drugs in humans has already been established.
Associate Professor Puya Gharahkhani, the lead author from QIMR Berghofer, highlighted the significance of these findings in developing a genetic test to predict an individual’s risk of developing glaucoma.
“Glaucoma is one of the most strongly genetic of all human diseases. We can use our genetic discoveries to identify those who are at higher risk.
“If we can find people before the disease develops, we can prevent blindness in those people,” Professor Gharahkhani added.
To enhance the accuracy of their genetic prediction tool and identify more genes associated with glaucoma risk, the researchers aim to collect additional data. Over 5,000 Australians have already volunteered for the QIMR Berghofer Genetics of Glaucoma study, but more participants are needed.
Professor MacGregor urged individuals with a personal or family history of the disease, particularly those aged 50 to 65 without glaucoma but with a close relative (parent or sibling) who has the disease, to sign up for the study.
He emphasized, “We want to prevent glaucoma from robbing people of the ability to drive and read and recognize their loved ones, but we need your help to do this.”
The ultimate goal is to make the genetic test available to everyone in the community in the near future.
Prior genetic studies on glaucoma have primarily focused on individuals of European ancestry. However, since glaucoma rates are highest among people of African and Asian ancestry, this research incorporated data from diverse populations on an unprecedented scale.
Associate Professor Gharahkhani added, “The global nature of our data allowed us to identify a large number of glaucoma risk genes, and to also discover that most of those genes are actually shared across different ethnic ancestry groups.
“This means that genetic tests for glaucoma are likely to work well across a wide range of ancestries.”
The research involved collaboration with the International Glaucoma Genetics Consortium (IGGC), which aims to expand knowledge about the genes influencing glaucoma by pooling global data sets from genome-wide association studies.
Moreover, the research uncovered, for the first time, associations between glaucoma risk and diabetes as well as immune diseases like multiple sclerosis.
Professor MacGregor revealed that some drug discovery work suggests existing treatments for other diseases, such as the diabetes drug Metformin, may hold potential for use in glaucoma.
“Some of our drug discovery work suggests that certain existing treatments for other diseases, such as the diabetes drug Metformin, may have potential for use in glaucoma,” Professor MacGregor added.
Image Credit: Shutterstock