Nav: Home

UAlberta scientists first to pinpoint a cause of pigmentary glaucoma

January 30, 2019

An international team of researchers has identified a gene responsible for the onset of pigmentary glaucoma, which may lead to new therapies for the condition.

"People who traditionally we wouldn't think of having glaucoma--young males in their 20s and 30s--are at particular risk for this form of the disease and of losing their vision," said Michael Walter, professor and chair of medical genetics at the University of Alberta.

It is the first time a cause of the disease has been identified.

Pigmentary glaucoma (PG) occurs when the pigment on the back of the iris gets deposited into the front part of the eye, causing vision loss and eventually blindness if left untreated. It's estimated that at least 150,000 people in North America are affected by the condition.

The study, led by Walter, also involved researchers at Harvard University and Flinders University in Australia. The team, using data from two individual families with a predisposition toward PG, used a technique known as whole exome sequencing to identify the premelanosome protein (PMEL) gene as one associated with pigmentary glaucoma. The finding was further confirmed through detection of more PMEL gene mutations following the examination of 400 additional patient samples.

The researchers determined the mutations in the PMEL gene had biological consequences, using a series of biochemical and cell biology tests to show that most of the mutations significantly altered human cells. Collaborating with Ted Allison, an associate professor of medical genetics at the U of A, the team used gene-editing technology called CRISPR Cas9 to introduce the mutations into the DNA of zebrafish.

"We found that these fish had altered pigmentation and eye defects which were very reminiscent of human glaucoma," said Walter. "Altogether, the findings showed us quite clearly that we have identified a new gene that causes glaucoma.

"I think the collaborative effort we've had in this research has really let us explore this more fully than any one lab could have done."

Walter, who is also a member of Alberta Vision Net, which brings together researchers from the universities of Alberta and Calgary to advance the understanding and treatment of ocular disease, is now focused on efforts to better understand how the mutations lead to pigmentary glaucoma. He said the research also identified unexpected similarities to other neurodegenerative diseases such as Alzheimer's, which could lead to exciting new possibilities for treatment.

"It opens up awareness about other approaches we could take," said Walter. "Potentially some of the methods that are currently being used to think about treating Alzheimer's might even be applied to treat glaucoma."
-end-
The research, which was published in Human Molecular Genetics, was supported by funding from the Royal Alexandra Hospital Foundation, Canadian Glaucoma Research Society, Alberta Vision Network, Canadian Institutes of Health Research, Maternal and Child Health Student Support, the BrightFocus Foundation, the March of Dimes Foundation and the National Institutes of Health.

University of Alberta Faculty of Medicine & Dentistry

Related Glaucoma Articles:

Long-term statin use associated with lower glaucoma risk
A new study brings the connection between statin use and risk of glaucoma into sharper focus.
Health burden of glaucoma has risen worldwide
The health burden of glaucoma has continuously increased around the globe in the past 25 years, according to an Acta Opthalmologica study.
UAlberta scientists first to pinpoint a cause of pigmentary glaucoma
An international team of researchers has identified a gene responsible for the onset of pigmentary glaucoma, which may lead to new therapies for the condition.
Using EHR-linked medication reminders for glaucoma patients
Mobile device reminders have been associated with better medication adherence and linking reminders to patient electronic health records (EHRs) could potentially allow some oversight by clinicians.
Traditional glaucoma test can miss severity of disease
The most common test for glaucoma can underestimate the severity of the condition by not detecting the presence of central vision loss, also known as macular degeneration, according to a new Columbia University study.
More Glaucoma News and Glaucoma Current Events

Best Science Podcasts 2019

We have hand picked the best science podcasts for 2019. Sit back and enjoy new science podcasts updated daily from your favorite science news services and scientists.
Now Playing: TED Radio Hour

Erasing The Stigma
Many of us either cope with mental illness or know someone who does. But we still have a hard time talking about it. This hour, TED speakers explore ways to push past — and even erase — the stigma. Guests include musician and comedian Jordan Raskopoulos, neuroscientist and psychiatrist Thomas Insel, psychiatrist Dixon Chibanda, anxiety and depression researcher Olivia Remes, and entrepreneur Sangu Delle.
Now Playing: Science for the People

#537 Science Journalism, Hold the Hype
Everyone's seen a piece of science getting over-exaggerated in the media. Most people would be quick to blame journalists and big media for getting in wrong. In many cases, you'd be right. But there's other sources of hype in science journalism. and one of them can be found in the humble, and little-known press release. We're talking with Chris Chambers about doing science about science journalism, and where the hype creeps in. Related links: The association between exaggeration in health related science news and academic press releases: retrospective observational study Claims of causality in health news: a randomised trial This...