Genetic Risk Score Detects Glaucoma and Predicts Progression of the Disease

Establishment of a glaucoma polygenic risk score (PRS) will facilitate the development of a personalized approach for earlier treatment of high-risk individuals, with less intensive monitoring and treatment being possible for lower-risk groups.

Glaucoma is a group of eye diseases, which cause damage to the optic nerve that can result in vision loss. The most common type is open-angle glaucoma, in which the drainage angle for fluid within the eye remains open, with less common types including closed-angle glaucoma and normal-tension glaucoma. Open-angle glaucoma develops slowly over time and there is no pain. Peripheral vision may begin to decrease, followed by central vision, resulting in blindness if not treated. Closed-angle glaucoma can present gradually or suddenly. The sudden presentation may involve severe eye pain, blurred vision, mid-dilated pupil, redness of the eye, and nausea. Vision loss from glaucoma, once it has occurred, is permanent. Risk factors for glaucoma include increased pressure in the eye, a family history of the condition, and high blood pressure.

Investigators at QIMR (Queensland Institute of Medical Research) Berghofer Medical Research Institute (Brisbane, Australia) and Flinders University (Bedford Park, Australia) reported that they had identified 107 genes that increased a person's risk of developing glaucoma.

The investigators found that individuals in the top PRS decile reached an absolute risk for glaucoma 10 years earlier than the bottom decile and were at 15-fold increased risk of developing advanced glaucoma. Furthermore, the PRS predicted glaucoma progression in prospectively monitored, early manifest glaucoma cases and surgical intervention in advanced disease.

"Glaucoma is a genetic disease and the best way to prevent the loss of sight from glaucoma is through early detection and treatment," said senior author Dr. Stuart MacGregor, head of the statistical genetics group at QIMR Berghofer Medical Research Institute. "Our study found that by analyzing DNA collected from saliva or blood, we could determine how likely a person was to develop the disease and who should be offered early treatment and or monitoring. Importantly, unlike existing eye health checks based on eye pressure or optic nerve damage, the genetic test can be done before damage begins so regular screening can be put in place. Having a high risk score does not mean you will definitely get glaucoma, but knowing you could be at future risk allows people to take the necessary precautions."

"We want to know who will get glaucoma, and for those who are susceptible, we want to be able to pinpoint at what age they are going to get it," said Dr. MacGregor. "That would allow us to develop a personalized approach for earlier treatment of high-risk individuals, and mean people at lower risk could have less intensive monitoring and treatment. This would have benefits for patients, doctors and the health care system with reduced interventions and reduced costs."

The paper was published in the January 20, 2020, online edition of the journal Nature Genetics.

Related Links:
QIMR Berghofer Medical Research Institute
Flinders University