Inherited Retinal Diseases: Dispelling stigma and the importance of genetic testing
Posted September 29, 2023 6:24 pm.
Last Updated September 29, 2023 8:25 pm.
Inherited Retinal Diseases (IRD) affect more than 20,000 Canadians and there are no treatments for the progressive conditions.
They are a large group of hereditary eye conditions caused by varying gene mutations and can be diagnosed in childhood, adolescence or later in life depending on the specific disease.
“I’ve had low vision since I was born …[I’m] completely night blind pretty much,” explains Ramya Amuthan, born with Leber’s Congenital Amaurosis (LCA) — one of many IRDs that result in partial or complete blindness.
“My peripheral vision is very poor. I can’t see stairs and things around me and I also have central vision loss.”
LCA is a recessive condition, which means both of Amuthan’s parents carry the mutated gene associated with the disease.
“My brothers are both carriers, but they don’t have the eye condition. It basically runs in the family,” she says.
Now an advocate for people with disabilities, Amuthan says for the first 18 years of her life, she did not identify as disabled.
“I would walk around the Sri Lankan – Tamil community as if I didn’t have a disability. I would grab my mom’s arm or my brother’s arms, but I would never even consider pulling out my white cane at community events … it was a don’t-ask-don’t-tell, elephant in the room situation,” she says.
“I’m sure people knew that I had a disability of some sort, they can probably connect the dots, but nobody would bring it up. It was absolutely taboo to present yourself as a fully accepting person with a disability.”
In a community environment where she felt she had no choice but to hide her disability, Amuthan says she learned to “pass” as a sighted person.
“I wanted to work. I wanted to sit around and eat with people and have normal conversations. But if you were disabled, there’s this internalized trauma and ableism that you are not going to be treated as equal to everybody else,” she says.
“And this is not just exclusive to the Sri Lankan, Tamil community. For generations and generations, if you had a disability, you just weren’t a part of society. And therefore that trickles down to how you will now identify as a person with a disability — which is that, ‘oh, I know that this is a way too difficult for people to handle, so I’m just gonna pretend not to be disabled.'”
After years of silence, Amuthan says she slowly began becoming more open about her condition when she left home to live on her own and started making efforts to dispel the stigma surrounding her condition, both in her community and beyond.
“We’re not pushing the needle forward by everybody pretending like a problem or a situation or an experience doesn’t exist,” she says.
“People believe that living with a disability is just the worst that could possibly happen to you … and obviously that kind of attitude is one of the biggest barriers people with disabilities are facing in order to move towards this inclusive world. All we’re trying to do is just live our lives and that comes with some accommodations [but] we’re trying to squeeze ourselves into workplaces and educational spaces and recreational activities in order to live a full life just as everybody else.”
Amuthan says another big misconception is that all those who identify as blind have zero vision.
“That is absolutely not true. I would say I am right in that crack where at night I can’t see anything, I can’t rely on any usable vision that I have, but during the day, I actually have quite a bit of usable vision that I can use to travel to identify people and just navigate life day-to-day. And so I use a combination of my sight as well as sight alternative senses to do a lot of things.”
Amuthan is also working to raise awareness about the importance of getting tested for IRDs — which can only be confirmed with a genetic test.
“It’s really one of the only ways to figure out what’s going on with your body and with your family,” she says.
Genetic testing for Inherited Retinal Diseases
Dr. Larissa Moniz, the Director of Research Admission Programs at Fighting Blindness Canada says testing for an IRD starts with a clinical test at an eye doctor.
“They’ll look through at your eye — how healthy the front of your eye is, how healthy the back of your eye is. They might do some more complicated tests to understand how the actual cells are working,” she explains.
“They talk to you about any symptoms — are you losing any vision? Are you having blurriness, are you having blotchiness? That sort of gives them some idea about your potential clinical diagnosis.”
If the eye doctor concludes that based on clinical characteristics and any symptoms, the patient might have and IRD, genetic testing is recommended to confirm the diagnosis and determine the type of IRD.
“Until you have a genetic diagnosis, it’s hard to sometimes definitively say that it is an inherited retinal disease. And so having the genetic diagnosis tells you that, but it can also give you some information about how your disease may progress. Will it go very quickly? Will it go more slowly? It can also help your family understand more about the inheritance. So for instance, do other family members want to get tested? It can also help for family planning,” says Moniz.
“For individuals, it might change the choices they can make around education, around their career choices, around day-to-day activities.”
A genetic test involves the collection of a blood or saliva sample that is used to examine the patient’s DNA and is covered by provincial health insurance in Canada.
“Everybody’s DNA is made up of a string of letters. So what they’re doing is they’re seeing are there any letters that have changed compared to the average population. Sometimes the change doesn’t mean anything and it doesn’t impact the gene at all, but sometimes the change can really impact how the gene functions, explains Moniz.
She adds that genetic testing is not a one-and-done process.
“About 20 or 30 per cent of people who have an Inherited Retinal Disease will not get a positive result on their genetic test. And that’s because we might not have identified the genetic mutation yet. So every year scientists are discovering more and more genes that could lead to an inherited retinal disease,” she says.
“What we suggest for people who may have been [clinically] diagnosed with an inherited retinal disease but haven’t received a genetic diagnosis is that if it’s been about over five years, you might want to talk to your doctor about if it’s appropriate to go for another test.”
Moniz says another important reason to get genetically tested is because while there are no current treatments for IRDs, there are some in the pipeline.
“Some of the most promising [treatments] are gene specific and the only approved therapy for Inherited Retinal Disease is gene specific. So knowing your genetic diagnosis allows you to potentially join a clinical trial or get treatments if they get approved in Canada,” she says.
Participating in a clinical trial is why Amuthan first opted for genetic testing.
“There’s a lot of that ripple effect that comes and stems from genetic testing,” she says.
“You might not even be aware that you have an eye condition that’s recessive that’s going to come about in a couple years. You might not know that you have Retinitis Pigmentosa (RP) — which usually shows up in your thirties or forties — but you’re in your twenties or in your teens and you or your family or your lineage have no idea that’s what you have.”
Click here to learn more about genetic testing for IRD.