Genetic discovery in juvenile glaucoma

A major international study has identified a genetic contributor to juvenile glaucoma.

Published in JAMA Ophthalmology, the findings add to a growing body of evidence about what causes glaucoma and mark another important step towards treating multiple forms of the disease, supported by genetic testing, said Flinders University authors Professor Jamie Craig, Dr Emmanuelle Souzeau and PhD candidate Giorgina Maxwell.

“This study highlights the potential for routine testing of FOXC1 [gene] duplication as part of the genetic testing process, particularly in families with a history of this form of juvenile glaucoma,” said lead author Maxwell, a genetic counsellor at Flinders University’s Department of Ophthalmology.

“This is important information for family members too. If a person is found to have the extra copy of the gene, their first-degree blood relatives – parents, siblings and children – have up to a 50% chance of also having it.

“Identifying family members who are at risk allows earlier monitoring and treatment, helping to prevent vision loss from glaucoma,” she said.

To assess the prevalence of FOXC1 duplication and its presentation, a total of 594 juvenile open-angle glaucoma patients were tested using genetic databases from Massachusetts Eye and Ear in the US and the Australia and New Zealand Registry of Advanced Glaucoma (ANZRAG). Researchers identified 20 individuals from 10 families with the duplicated gene.

“Across these two large databases, this specific genetic duplication appeared frequently, confirming its connection to this condition, which is often difficult to diagnose,” said Prof Craig, co-director of the Flinders Health and Medical Research Institute Eye and Vision group.

Juvenile glaucoma is often underdiagnosed, said Dr Souzeau, who conducts screening for ANZRAG. “Identifying the genetic cause in these families is critical for diagnosis and prevention.”