Hereditary blindness could be cured after major research breakthrough

Researchers are one step closer to developing effective therapies for hereditary blindness after discovering hundreds of new genes linked to the health condition.

The breakthrough is being hailed as “extremely valuable” for people living with hereditary blindness and the information unearthed in the University of California Davis study will immediately be put into practice by those working in ophthalmic community.

The findings were published in Nature Communications Biology. 

For their study, researchers teamed up with the International Mouse Phenotyping Consortium, of which UC Davis’ Mouse Biology Program is a founding member. The consortium has been practising groundbreaking genetic work on mice, creating lines of “knockout” mice that lack a single specific gene, such as those linked to eyesight, and screening them for their effects.

To date, the consortium has generated more than 7,000 strains of gene-knockout mice, of which 4,364 have been characterised across 11 organ systems.

Analysing data gathered from these genetically modified mice enabled UC Davis researchers to discover 261 new genes that are linked to eye and vision defects.

They identified 347 genes altogether, of which 86 were either well-established as involved in eye disease or were associated with vision in some way. Three-quarters of the genes — 261 — were not previously known to cause eye disease in any species.

Ala Moshiri, associate professor of ophthalmology and vision science at UC Davis, said the findings could lead to effective treatments for hereditary blindness, and were a positive indicator that mysteries surrounding other hereditary diseases could also be untangled in future.

“In 2018, if someone has a form of hereditary blindness, we can identify the cause 50 to 75 percent of the time,” Moshiri said. “In the remaining cases, we know the mutation is there but we don’t know where to look. Now eye centres that do DNA sequencing can call back patients and screen them for these new genes.”

While the mouse and human genomes clearly differ, most human genes have an analogous counterpart in mice. The UC Davis team is collaborating with eye centres at Baylor College of Medicine in Houston and the University of Iowa to check the newly identified mouse genes against their human equivalents, Moshiri said.

The new genetic information could also enable new therapies for hereditary eye disease. In 2017, the FDA approved the first gene therapy for any disease — treating hereditary blindness caused by a defect in the retinal gene RPE65.

“We expect that more and more of these genetic diseases will be treatable,” Moshiri said.