eyesongenes campaign: how genetic testing can improve diagnosis and treatment of inherited retinal diseases
more than eight million canadians are living with an eye disease that could lead to blindness, according to fighting blindness canada.
6 minute read
we apologize, but this video has failed to load.
try refreshing your browser, or
tap here to see other videos from our team.
tap here to see other videos from our team.
ruanne lai, a scientist, cellist and lover of the outdoors doesn’t let her vision loss hold her back. the new westminster, b.c. woman is active with her two young kids, works as a research facilitator at the university of british columbia, and adores her guide dog, portia.
“she is so great and so lovely. i’ve had her for two and a half years,” lai, 41, says of her dog always at her side. “before i had her, i used a mobility cane.” she explains that canes are helpful at identifying where not to go, like walking into walls or obstacles, but portia helps her find street curbs and navigate construction sites, for example. “i have a little central vision, so sometimes it’s hard for me to find where the door is. so, she’ll help me find the door, find the chair, find the stairs.”
lai has a form of retinitis pigmentosa, a genetic disease that makes light-sensitive cells in the retina at the back of the eye break down slowly over time, which stops them from working. retinitis pigmentosa isn’t common, but part of a group of rare inherited retinal diseases that affect the retina and ultimately lead to blindness for most people. basically, you’re born with it, but symptoms may not be noticed until later in childhood or as adults.
advertisement
how rare? there are about 21,000 canadians who have an inherited retinal disease – but they may not know exactly what their eye problem is. more than eight million canadians are living with an eye disease that could lead to blindness, according to fighting blindness canada.
lai was 12 when she first noticed that she wasn’t able to run and play as easily as her friends but wasn’t diagnosed until years later – she had a genetic eye test in 2010 that confirmed her disease. her mother in taiwan also has the disease and lives independently, and her brother, in his mid-40s, was recently diagnosed as well.
adapting to disability and getting creative in how she does things – along with learning braille with her kids, seven and nine – is part of her day-to-day mindset.
“i think it’s a test of being more patient with yourself and having more self-compassion. i can’t sight read as fast as i would like to or have previously done, but that’s okay,” she says of playing cello by ear and memory instead of reading notes on sheet music.
“you don’t focus on the loss. you focus on the gains and teaching your children to have more compassion.”
lai is sharing her story in a video for a new campaign supported by fighting blindness canada to spread the word about the availability and importance of genetic eye testing (which is publicly funded in all provinces and territories). the information hub at eyesongenes.ca was developed by johnson & johnson canada.
advertisement
genetic eye testing takes a sample of your dna, from blood or saliva like a cheek swab, and examines it in a lab to try to identify changes or mutations that have caused vision loss. the testing for inherited retinal diseases has made significant strides over the last decade, as scientists have discovered more than 300 genes responsible for these diseases.
as fighting blindness canada points out, some inherited retinal diseases like choroideremia or x-linked retinoschisis are caused by one or only a small number of genes, while others are caused by many different mutations in many different genes. to date, more than 64 genes have been identified that cause retinitis pigmentosa. but for many people, the gene responsible for their condition has not been identified yet.
another key reason to have the test is the potential to get involved in clinical trials that are gene specific, so the first step to determining your eligibility could be genetic testing or knowing your gene mutation.
as larissa moniz, director of research and mission programs at fighting blindness canada explains, genetic eye testing used to be limited to research purposes, but now it’s playing a role in treatment development and clinical trials. there’s recognized value in testing and outcomes that will impact people with eye disease.
advertisement
“now we have over 300 genes, which means it’s easier to get a diagnosis. you can really pinpoint what the gene mutation is and you can confirm it’s an inherited retinal disease. and even more importantly, this information is now starting to turn into treatments for inherited retinal diseases through gene therapies. so there’s an almost clear link between research to understand genes and now getting the first treatments for inherited retinal diseases, which are gene specific.”
in the research space, gene therapy for inherited disorders is moving forward in clinical trials with proven success. moniz highlights one of the first gene therapies for inherited retinal disease approved by health canada in 2020 and in practice in 2023.
“the first gene therapy for an inherited retinal disease is something that’s called a gene replacement therapy,” she says. “most of the inherited retinal diseases are caused by a single gene that’s mutated, not for everybody, but for most people. because of that, you know exactly what is causing the disease – versus cancer where you might have multiple different mutations and multiple different genes.”
in gene replacement therapy, the faulty gene is replaced with a healthy copy of the gene to help the cells do the job they need to do. the aim is to correct the underlying cause of the disease potentially for a lifetime. the working genes can be delivered to eye cells in the retina during a same-day procedure.
advertisement
moniz, who has a phd in molecular biology, also talks about the eye as a model system for gene therapy because specialists can go more directly into the eye for gene therapy in a very specific place compared to treatment “in the brain or something in the liver, where it’s much harder and you might have impacts on many different parts of the body. it’s about where the eye is and that’s why we’re seeing some of the therapies being first in the eye.”
knowing exactly what gene is responsible for such a disabling disease is empowering for people who have to make changes in their lives as the disease progresses. in many inherited retinal diseases, you lose your peripheral vision first where you have a harder time seeing in the dark or your peripheral vision is getting smaller and smaller until you end up with a narrow band of tunnel vision. others lose their central vision first and then the peripheral vision will go afterward.
when you know more definitively what’s causing all this, you can follow the research to see what’s coming and stay informed, moniz says. she encourages people to get genetic eye testing and connect with organizations like fighting blindness canada for resources and support.
advertisement
“getting diagnosed with inherited retinal disease can be a really stressful time. you might have a lot of questions. there are resources out there. we have different events where you can come learn about your eye disease, but also meet other people who are going through a similar thing that either you or your child is. although these are rare diseases, there is a lot of community connection out there.”
and for lai, genetic eye testing has allowed her to contribute to the science of exploring inherited retinal disease and therapies that could come to market.
“it is important to do genetic testing because it adds another piece of understanding your medical condition,” she says. “you are also raising your voice and being heard because genetic testing has really boomed in the past five years. it’s just going to keep going.”
share story
