Optic Nerve Structure and Gene-Environment Association

David Mackey, MD Royal Victorian Eye and Ear Hospital

Summary

What genes affect the optic nerve and put it at risk of glaucoma? Knowing which gene changes increase the risk of glaucoma will enable us to diagnose people early and start treatment to prevent blindness.

We have previously measured photos of the optic nerve of 1,400 20-year olds and identified genes associated with the size of their optic nerves. We now propose to analyze high-resolution scans of the same nerves to search for new genes.

Project Details

Glaucoma is a complicated disease in which the optic nerve becomes damaged, resulting in permanent vision loss. The aim of our project is to identify new glaucoma risk genes that will not only help to improve our understanding of what causes the disease, but potentially enable us to develop new treatments.

Our research is focused on better understanding the anatomy and genetics of the optic nerve head: this is the part of the eye damaged in glaucoma. We are using powerful new imaging technology called spectral domain optical coherence tomography (SD-OCT) to take 3D photographs of the internal anatomy of the optic nerve head. From these images, we are able to measure the size and shape of the optic nerve head structures more accurately than previous methods of measurement.

Ours is the first study we are aware of that combines SD-OCT measurements and genetic association techniques to look for new glaucoma genes. Previous research has shown that many different genes may be responsible for disease development. In that sense the genetics of glaucoma may be thought of as a jigsaw puzzle; we have some of the pieces in place, but many more to find and fit. By studying the genetic variation of the internal anatomy of the optic nerve head, our project will add to the existing knowledge of what causes glaucoma and contribute more pieces to the puzzle.

This project will have important implications for glaucoma diagnosis and management. Not only do we hope to be able to diagnose the disease earlier, therefore commencing treatment and preventing vision loss earlier, but the identification of new glaucoma genes may allow for the development of novel treatment options.