Glaucoma is the world’s leading cause of irreversible blindness, with primary open-angle glaucoma (POAG) being the most common type. POAG causes gradual damage and death to retinal ganglion cells (RGCs), leading to peripheral (side) vision loss. RGCs communicate visual information to your brain through the optic nerve. 

In an effort to identify new treatment targets, a team of Australian researchers used stem cell models to compare the genetic differences of RGCs in people with POAG versus people with healthy eyes. The team’s results have important implications for people living with glaucoma.*

What the researchers did

Until recently, this type of research in glaucoma hasn’t been possible, since it would have involved invasive removal of RGCs from living donors. In this study, however, the researchers were able to employ a clever workaround with Nobel Prize-winning technology. 

• They examined 110 people: 56 healthy and 54 with POAG. The two groups were fairly matched in age, and both groups were about evenly split between men and women.
• The scientists used stem cells (made from reprogrammed skin cells) to produce nearly a quarter million new RGCs.
• The team then created a genetic map and looked for unique features that might promote vision loss. 

What they found

By the end of the study, the team had found more than 300 unique genetic traits that they say deserve further research.

Study author Joseph Powell, Ph.D. of the Garvan Institute of Medical Research likens the genetic map of glaucoma to a “road network with traffic lights.” Looking at the map, he says, his team can see which genes are turned on, which are turned off, and which are “blinking,” indicating different levels of activity. 

To help find better treatments, Powell says, the next step is to find out “which of these traffic lights should be turned off or on.”

What it means

Lead study author Alex Hewitt, Ph.D., MBBS, Head of Clinical Genetics at the Centre for Eye Research Australia (CERA), said the study provides researchers with hundreds of new drug development targets. Current treatments are based on reducing eye pressure, which helps slow progression but doesn’t cure glaucoma or repair existing damage. 

“The rich source of genetic information generated by this research,” Hewitt concludes, “is an important first step towards developing new treatments that go beyond lowering eye pressure and can reverse damage and vision loss.”

*University of Melbourne. (2022, June 9). Stem cell research reveals detailed genetic roadmap of glaucoma. ScienceDaily. https://www.sciencedaily.com/releases/2022/06/220608112524.htm