Genetics and extensive schooling likely cause nearsightedness in children

Researchers have discovered five genetic variations that, the longer a person attends school, increase their risk of developing nearsightedness. These results were published on November 17^th, 2022 in the open-access journal PLOS Genetics by a team at Cardiff University in the United Kingdom, led by Jeremy Guggenheim.

As a leading contributor to irreversible vision loss in older people, nearsightedness is linked to a variety of eye conditions. However, children are frequently affected by nearsightedness, and the condition seems to be a combination of genetics, a lack of outdoor time, and extensive schooling.

More than 450 genetic variants have been found in genetic studies to be linked to a higher risk of nearsightedness, but only a small number have been shown to specifically increase risk in individuals with the linked lifestyle factors. Researchers used more than 340,000 participants with European ancestry genetic and health information in the new study.

They conducted a genome-wide analysis to find genetic variations that, in combination with rigorous academic training, increase a person’s risk of developing nearsightedness.

The study found five genetic variations that, the longer people spent in school, especially those who had graduated from college, gradually increased their risk of developing nearsightedness.

Two of these variants were discovered in studies of East Asian cohorts, where about 80% of children develop nearsightedness, while three of these variants were previously unknown.

For comparison, in the West, nearsightedness affects about 30% of children. The findings, according to the researchers, offer fresh insights into the biological processes that underlie nearsightedness, but further study is required to comprehend how those processes interact with dietary and lifestyle choices to produce the condition.

As well as requiring the need for glasses or contact lenses, myopia is a leading cause of uncorrectable visual impairment. Building on our previous research linking education and myopia, the new study identifies 5 genes associated with myopia development whose effects are amplified by additional years spent in education.”

Jeremy Guggenheim, Professor, Myopia Research, School of Optometry and Vision Sciences, Cardiff University