Genetic testing underutilized in rare retinal diseases

Shortcomings in knowledge may limit the number of patients undergoing genetic testing for inherited retinal diseases (IRDs), which can lead to reductions in vision and blindness, according to a recent article in the Orphanet Journal of Rare Diseases.

Early and accurate diagnosis can help improve patient outcomes, but clinical diagnosis can be difficult due to the overlapping characteristics of many IRDs. Despite the benefit of genetic testing in establishing a clear diagnosis, it is often underutilized.

One retrospective analysis of genetic testing utilization found that although most providers felt genetic testing was useful in IRD management, only 1.5% of 207 individuals with IRDs had genetic testing ordered by their ophthalmologist.

Another shortcoming highlighted in the article is the lack of genetic counselors with expertise in ophthalmology. Of the approximate 5000 certified genetic counselors in the United States, <1% have expertise in ophthalmology, which is a problem due to the “high genetic heterogeneity, overlapping clinical presentations, and variability in inheritance patterns,” found with IRDs that make molecular diagnostic difficult.

The authors suggest that ophthalmologists who suspect their patient may have an IRD should collaborate with an ocular genetic counselor or IRD specialist.

“With the complexity of IRDs, collaboration with specialists may allow for improved decision-making regarding the most appropriate genetic test panel, pre- and post-test counseling, and accurate interpretation of the test findings in the context of the clinical diagnosis,” they wrote.

Reference
Lam BL, Leroy BP, Black G, et al. Genetic testing and diagnosis of inherited retinal diseases. Orphanet J Rare Dis. 2021;16(1):514. doi: 10.1186/s13023-021-02145-0. PMID: 34906171; PMCID: PMC8670140.

–Kelsey Moroz