New opportunities towards gene therapy and diagnosis for the blinding eye disease, retinal dystrophy, may now become available following work done by the Eye Genetics Research Unit at Children’s Medical Research Institute.

This work was published in the Journal of Personalized Medicine today.

The team looked at the RPGR gene which is involved in maintaining healthy photoreceptor cells. Variants in this gene are the main contributor to eye disease such as rod cone dystrophy and gene therapy for this condition is now in clinical trials.

Rod cone dystrophy affects rod and cone photoreceptor cells and manifests in decreased night and peripheral vision and progressive vision loss. There are more than 60 identified contributing disease genes.

CMRI’s Eye Genetics team investigated a novel genetic variant in the RPGR gene in a patient who has rod cone dystrophy and, working alongside CMRI’s Stem Cell Medicine team, used induced pluripotent stem cells to produce retinal organoids. This work found that the novel variant impacted the function of the gene.

Head of CMRI’s Eye Genetics Research Unit, Professor Robyn Jamieson said the first and second authors Fidelle Karam and To Ha Loi had put in tremendous work to show that this genetic variant was disease-causing, and they had now identified biomarkers to further investigate novel therapies directed at variants in the RPGR gene.

“There is potential for clinical trials in the future for genetic therapies related to disease caused by variants in RPGR, so this work provides a genetic diagnosis, as well as avenues for investigation and biomarkers for investigation of new therapies for people with variants in this gene – which is one of the most common causes of retinal dystrophy.”

The CMRI team worked closely with collaborators at the Department of Clinical Genetics and Sydney Genome Diagnostics, Western Sydney Genetics Program, Sydney Children’s Hospitals Network (SCHN), and the Rare Diseases Functional Genomics Laboratory, SCHN and CMRI, and Save Sight Institute, Faculty of Medicine and Health, University of Sydney.

This research was supported by the Ophthalmic Research Institute of Australia, Cure Blindness Australia, The Hill Foundation and an NHMRC grant. It was also supported in part by Luminesce Alliance - a not-for-profit cooperative joint venture between Sydney Children's Hospitals Network, CMRI and Children's Cancer Institute.