A recently generated polygenic score can quantify an individual’s genetic susceptibility to refractive error; however, it is most effective for those of European descent. Photo: Getty Images.

Increased attention to the ocular health risks of high myopia in recent years has eye doctors more vigilant for early signs. Though clinical examination and refraction are the mainstays, more advanced diagnostic concepts are also being considered. Developing a polygenic risk score has been proposed as a potential tool to quantify susceptibility to refractive error and identify children with an increased risk of high myopia. However, current efforts have lacked the accuracy needed for clinical value. Recently, a team of researchers initiated a study to derive an improved polygenic score for this purpose. They also aimed to determine if this score was predictive of myopic macular degeneration—after accounting for spherical equivalent refractive error.

To identify studies on this topic, investigators conducted a literature search for the following keywords: “myopia” and either “polygenic” or “genetic risk.” A deep learning algorithm was then used to quantify the severity of myopic macular degeneration within the data those studies comprised. Prediction of high myopia was quantified as the area under the curve (AUC)—a statistical measure of the correspondence between variables—and prediction of severe myopic macular degeneration was assessed by logistic regression, according to the study authors.

Data showed that, in independent samples of European, African, South Asian and East Asian ancestry, the score explained 19%, 2%, 8% and 6% of the variation in spherical equivalent refractive error, respectively.

Study authors reported that the AUC for high myopia in these samples was 0.78, 0.58, 0.71 and 0.67, respectively. They also found that a polygenic score for refractive error was not predictive of myopic macular degeneration after accounting for spherical equivalent refractive error.

The polygenic risk score studied here “has a level of accuracy approaching that required for clinical utility in predicting children at risk of high myopia, but only for children of European ancestry,” the study authors suggested while discussing the implications of their work in eBioMedicine.

Clark R, Sze-Yee Lee S, Du R, et al. A new polygenic score for refractive error improves detection of children at risk of high myopia but not the prediction of those at risk of myopic macular degeneration. eBioMedicine. April 11, 2023 [Epub ahead of print].