Wear Glasses? Genetic Mutation May Cause Your Nearsightedness

Do you wear glasses or contact lenses? Then you may have a genetic mutation. Researchers have discovered mutations in a gene that's associated with a severe form of nearsightedness. The finding could give rise to better understanding the condition and developing future treatments.

Nearsightedness is also known as myopia, and is one of the most common human eye diseases in the world. It occurs when the eye is either too long, or the cornea has too much curvature. This, in turn, keeps light entering the eye from focusing correctly.

Yet a more severe form of this nearsightedness, called high-grade myopia, is what can really trouble patients. It affects up to two percent of Americans, and is especially common in Asian populations. It's caused by a combination of genetics and environmental factors, such as large amounts of reading. However, it can cause more severe eye problems such as retinal detachment, cataracts and glaucoma.

In order to find out the genetics behind myopia, researchers began by studying families with a history of high-grade myopia. They performed next-generation deep sequencing on four relatives from an 11-member American family of European descent. After analyzing DNA extracted from blood and saliva, they were able to identify mutations in the SCO2 gene in family members that possessed high-grade myopia.

"This is the first time a gene mutation for autosomal dominant nonsyndromic high-grade myopia in Caucasians has been discovered," said senior author Terri Young in a news release. "Our findings reflect the hard work and collaboration of our international team."

In the body, the SCO2 gene helps metabolize copper, an element that's important for regulating oxygen levels in eye tissue. Increased stress brought on by too much oxygen could alter the eye's development and function and, in turn, cause nearsightedness.

In fact, since normal copper metabolism is important for eye health, future research could focus on whether copper deficiency could place someone at a higher risk for nearsightedness. The findings could allow for better treatments for the eye disease--it could be as simple and easy as taking a supplement.

The findings are published in The American Journal of Human Genetics.