No-cost Programs Look to Widen Availability of Genetic Testing for Inherited Retinal Diseases
Individuals impacted by an inherited retinal disease (IRD) may have good reason to consider genetic testing, but the expense involved can be cost-prohibitive for some. In recent years, industry and non-profit-led initiatives have emerged to address this financial barrier, widen the availability of testing, and move research efforts forward.
IRDs are a group of rare diseases that can lead to severe vision loss or blindness, and each of these conditions is caused by at least one gene that is not working properly. They can affect people of all ages and progress at different rates, but many are degenerative with symptoms that continue to worsen over time.1
Traditionally, most IRDs are identified during childhood, explained Aaron Brock Roller, MD, a vitreoretinal specialist at Austin Retina Associates in Texas. But sometimes these diseases do not reveal themselves until later in life. “So it can really be picked up at any age,” he said.
Genetic testing can help pinpoint the gene causing an IRD, and knowing this underlying cause can be beneficial in a number of ways. It can help clarify or confirm an initial diagnosis, lead to a better understanding of risk factors for family members, or help lead to relevant clinical trials or treatments. This form of testing “has become the cornerstone of management for affected patients and family members,” said Dr Roller.
“Obtaining a molecular diagnosis opens the door for patients to better understand their condition and allows for an accurate assessment of risk to their children and other family members, which is often a primary patient concern,” he continued. “In some cases, testing can offer insight into disease prognosis and potential severity and can alert clinicians to the risk of associated systemic complications.”
Dr Roller pointed out that the development of treatment for IRDs is progressing quickly and predicted that therapy will continue to emerge for many patients in the years ahead. Genetic diagnoses can help determine eligibility for clinical trials and provide insight into possible therapeutic options.
“Diagnosis through genetic testing helps give patients hope that they may be eligible for treatment that can slow, avert, or even potentially reverse the progression of vision loss and can be profoundly beneficial to our patients,” he added.
For these reasons, Dr Roller recommends targeted genetic testing as well as test result interpretation and counseling from a qualified expert for patients with a diagnosis of IRD or suspicion of an IRD.
Testing Made Available to Patients at No Cost
The price tag of genetic testing can depend upon several factors, like the type of test, service provider, and health insurer involved. Although some insurers cover genetic testing, others do not. As a result, some interested patients may miss out because of this financial element. In recent years, however, industry and non-profit-led initiatives have emerged to make testing more readily available.
One example is the Inherited Retinal Disease Program. This no-charge genetic testing is available to people in the United States and Canada who are suspected of having an IRD or are at risk. The program provides testing with the Invitae Inherited Retinal Disorders Panel, which analyzes 330 relevant genes, and participants are eligible for genetic counseling made available by Invitae.2
Similarly, the My Retina Tracker Genetic Testing Program makes it possible for eye care professionals in the United States to order no-cost genetic testing and genetic counseling for patients who have been clinically diagnosed with an IRD. This partnership between the Foundation Fighting Blindness, InformedDNA, and Blueprint Genetics uses a 351 gene panel.3
Participants face no out-of-pocket costs for the test or counseling, and there is no charge to their insurance company, either. However, participants are responsible for the cost of any consultation or eye exams that are needed beforehand.4
Providing a Path Forward
The My Retina Tracker Genetic Testing Program “provides a really wonderful offering in terms of genetic testing and genetic counseling,” said Michelle Glaze, director of professional outreach for the Foundation Fighting Blindness. But she emphasized that it can also connect patients to the Foundation “for knowledge, community, and hope.”
When working with or providing care for a patient with an IRD, she said it is important for eye care professionals to provide a path forward. One example is recommending—or at least educating about—low vision and rehabilitation services. Even if a patient does not have severe vision loss when initially diagnosed, those services will become increasingly important for independence and daily living activities as an IRD progresses.
She also highlighted the My Retina Tracker Registry, a global database for patients impacted by IRDs. She referred to it as “a way for individuals with an inherited retinal disease to really stand up and be seen by the research community.”
Patients are needed for clinical trials, and this research is needed to study IRDs and find effective treatments, explained Ms Glaze, who was diagnosed with retinitis pigmentosa nearly two decades ago. Because IRDs are rare diseases, it can be difficult to find patients for clinical trials.
The registry helps facilitate this process, enabling a patient to be identified or recruited by researchers and companies that are pursuing the development of therapies. “So it really does bridge the gap between that patient community and treatments and cures,” she added.
Testing Limitations to Consider
Despite the benefits of genetic testing, there are limitations and potential drawbacks for patients and eye care providers to weigh as well. Genetic test results could cause anxiety for family members, for example, or the test results may fail to reveal the defective gene. So it can be especially helpful for patients to consult with a retinal doctor or genetic counselor before deciding whether or not to move forward.5
Researchers at the University of Oklahoma and the University of Southern California have examined the utility of no-cost genetic testing for patients diagnosed with an IRD. Their findings, published last year in the Journal of VitreoRetinal Diseases,6 revealed that about half of the patient samples (30 of 59) had a diagnostic yield. But nearly as many (28) were undetermined, and one patient received a negative result with no mutations or variants of uncertain significance identified.
“Open-access, no-charge panel testing offers a reasonable diagnostic yield,” the study authors concluded. “Accurate clinical diagnosis of IRD before testing and acknowledgment of the limitations of panel testing are critical.”
A genetic test that comes back with a negative result does not rule out the possibility that a patient has the disease in question, said Dr Roller. He highlighted Stargardt disease to help illustrate. The condition causes central vision loss progressively as a patient grows older, and it is traditionally discovered in children. But some patients have mild forms of the disease that goes unnoticed until later in life. When testing is eventually performed, the results are often inconclusive.
He explained that genetic testing relies on previously identified genetic mutations that are known to cause disease. When a test is performed, it compares a patient’s genetic profile to a list of potentially disease-causing mutations. The problem is that for any given IRD, only a subset of mutations has been identified.
In some cases, a patient may clinically have what appears to be consistent with a known IRD, yet their testing comes back without a positive result. In these instances, the individual may have the disease in question even though the database of known mutations hasn’t caught up. It is an issue that remains common for now, he added, although it is becoming less so over time as more and more mutations are identified.
–Paul Nicolaus
References
- Eye diseases & conditions: inherited retinal diseases. Prevent Blindness. Accessed January 27, 2023. https://preventblindness.org/inherited-retinal-diseases/
- Inherited retinal disease program. Invitae. Accessed January 27, 2023. https://invitae.com/en/sponsored-testing/ird
- My retina tracker genetic testing program. Blueprint Genetics. Accessed February 6, 2023. https://blueprintgenetics.com/my-retina-tracker-program/
- Genetic testing frequently asked questions. Foundation Fighting Blindness. Accessed January 27, 2023. https://www.fightingblindness.org/genetic-testing-faqs
- Why genetic testing is important. Foundation Fighting Blindness. Accessed January 27, 2023. https://www.fightingblindness.org/genetic-testing
- McClard CK, Pollalis D, Jamshidi F, Kingsley R, Lee SY. Utility of no-charge panel genetic testing for inherited retinal diseases in a real-world clinical setting. J Vitreoretin Dis . 2022;6(5):351-357. doi:10.1177/24741264221100936
