Abstract
Purpose :
Diagnosis of inherited retinal diseases (IRDs) by the use of ocular genetic testing has significantly evolved over the last 5 years. Here we retrospectively reviewed diagnosis and testing outcomes of IRDs patients seen in dedicated IRDs clinics over the last 5 years in a Midwest academic practice to better understand this unique population and their ocular genetic testing outcomes.
Methods :
Clinical records of all patients enrolled into an ocular genetics registry between June 2017 and July 2022 were reviewed for demographics, clinical diagnosis, and ocular genetic testing results.
Results :
Between June 2017 and July 2022, 696 patients with suspected IRDs were enrolled into an ocular disease registry with 96.1% having some form of genetic testing. 91% of individuals identified as white, and 45.3% were female. Most common ocular diagnoses were Retinitis Pigmentosa (36.7%), Stargardt (16.6%), Cone/Cone-rod dystrophy (7.7%), Choroideremia (5.5%) and Leber Congenital Amaurosis (3.9%). Causative genotype was found by genetic testing in 68.4%. Most common genes included ABCA4 (20%), USH2A (9%), CHM (8.3%), PRPH2 (6.3%), and RPGR (4.5%). Syndromic disease was identified in 18% with Ushers Syndrome (48.1%), Bardet Biedl Syndrome (15.6%) and Mitochondrial Disease(5.2%) being most common. A variety of different genetic panels were used for ocular genetic testing throughout the 5 years. Of the 208 genetically unsolved cases, 33 % had a suspicious variant of uncertain significance (VUS) and/or were missing a second allele in the setting of suspected autosomal recessive disease. 134 test results were updated during this time period, including 31 where updates resulted in a genotypic solved case. 17 patients had additional testing that resulted in 5 of these cases being genetically solved. Conclusive genetic testing was more common in those with syndromic IRDs, Caucasians and those younger than 40 years old.
Conclusions :
Genetic testing results for patients with IRDs can evolve over time with almost 20% of our cohort having updated results during a 5 year period. Additional targeted testing can also be helpful in genetically unsolved IRDs diagnoses. Awareness of the type of genetic testing initially performed and possible reclassification of variants overtime is important in management of IRDs patients undergoing genetic testing.
This abstract was presented at the 2023 ARVO Annual Meeting, held in New Orleans, LA, April 23-27, 2023.