Helping patients navigate the unsolved mysteries of genetic testing

Gene therapies were a popular part of the programme during the American Society of Retina Specialists (ASRS) annual meeting. But even as clinicians understand more about genetics and inherited conditions, unsolved mysteries prevent patients from receiving vision-saving care.

At this year's ASRS meeting in Long Beach, California, the Eye Care Network spoke with João Pedro Marques, MD, MSc, PhD, about his presentation. He is affiliated with Centro Hospitalar e Universitário de Coimbra in Coimbra, Portugal. Prof Marques spoke about inherited retinal diseases (IRD) and common challenges in genetic testing. He explained that genetic testing can be a pain point for clinicians and patients, and obstacles to accurate testing can have a major impact on the care patients receive.

"Even if you use state-of-the-art genetic testing, up to 30% of patients will remain genetically unsolved," he said. These inconclusive outcomes can be highly frustrating, Prof Marques explained. As such, his team conducted a retrospective, single centre study. Its goal was to identify baseline determinants which might predict ifi a patient's IRD can be genetically "solved" and attributed to a specific gene function.

In the study, over 800 patients with IRDs were classified into predetermined phenotypes.

"We found that the age of onset [being] before 18 years of age, the presence of familial consanguinity and the presence of a family history are actually significant determinants to obtain a positive genetic testing result," Prof Marques recounted. "If you put these factors all together, the likelihood of obtaining a positive test is even higher. However, if none of these factors are present, you'll get only a 30% chance of having a positive genetic testing result."

"Our main highlight is actually how real-world data can impact your daily clinical practice," he continued. "This is very important because of access to clinical trials and access to new gene therapies. If you don't have a genetic diagnosis, you won't be able to be enrolled in these kinds of treatments."

Watch the video to hear the complete findings in this new IRD research.