Australian researchers have been at the fore of the largest genetic study of glaucoma that has identified 44 new genetic variants that may lead to new treatment targets.
Ten Australian institutions involving some of the country’s most prominent glaucoma researchers were involved in the international effort which analysed genes in more than 34,000 people with glaucoma across multiple ancestries for the first time.
The results comparing the genes of people with the disease to 349,321 control subjects were published in Nature Communications last month.
In addition to identifying new genetic variants, the international consortium of researchers also confirmed 83 previously reported loci linked to glaucoma. Loci are considered “genetic street addresses”, denoting a specific location on a gene.
Lead author Mr Puya Gharahkhani, Associate Professor in the Statistical Genetics group at QIMR Berghofer Medical Research Institute in Brisbane, explained why – for the first time in a glaucoma genome-wide association study – they performed a cross-ancestry comparison looking at genetic data from people of European, African and Asian descent.
They found the majority of loci that contribute to glaucoma were consistent across all three groups.
“Glaucoma rates are highest in African and Asian ancestry groups, but the largest genetic studies of glaucoma in the past focused on people of European ancestry,” he said.
“Those studies showed genetic tests could be used to help identify who would benefit from sight-saving early monitoring or treatment, but because of the narrow scope of the genetic data, we weren’t sure until now that the genetic indicators were true for people of different ancestries.”
Future research will focus on using these genetic loci to improve screening and diagnosis of glaucoma and, one day, to develop new treatments.
“Glaucoma is one of the most strongly genetic human diseases, which is why we are looking at the genetic architecture of the disease to find clues on how to prevent and treat it,” Professor Stuart MacGregor, the head of QIMR Berghofer’s Statistical Genetics group and co-senior researcher on the study, said.
“We’re hopeful that understanding the biological processes and knowing which genes control them could help scientists develop new drugs in the future.”
Institutions in New South Wales that participated in the study included the Centre for Vision Research, Department of Ophthalmology and Westmead Institute for Medical Research, at the University of Sydney; Ophthalmology and Vision Science at Macquarie University; and Department of Ophthalmology at the University of Sydney, Sydney Eye Hospital.
In South Australia, the Department of Ophthalmology at Flinders University, and the South Australian Institute of Ophthalmology at the University of Adelaide were involved.
Menzies Institute for Medical Research at the University of Tasmania; the Centre for Eye Research Australia at the University of Melbourne; the Centre for Ophthalmology and Visual Science at the University of Western Australia; and QIMR Berghofer Medical Research Institute in Brisbane were also affiliated with the work.
Leading Australian researchers involved were Professor Alex Hewitt, Professor David Mackey, Associate Professor Paul Healey, Professor Paul Mitchell, Professor Robert Casson and Professor Ivan Goldberg.
Grants from the National Health and Medical Research Council (NHMRC) of Australia and the Ophthalmic Research Institute of Australia helped support the study.