A study recently published by researchers at Duke University has identified a gene mutation that causes near-sightedness, the News Observer.

The condition is clinically known as Myopia and around 30 percent of all Americans experience near-sightedness. What scientists have not been able to figure out about the disease thus far is why it can affect one sibling and not the other.

The Duke research team believe they've found the answer to that problem, a gene called SCO2.

Myopia is the most common eye disease in America, according to the American Optometric Association. The condition is caused by the eye being oval-shaped rather than being round or, in some cases, the cornea being too curved. Regardless, the condition makes it hard for the eye to focus properly the light coming through the pupil.

Myopia's main symptom is blurred vision and it can come with varying degrees of severity. SCO2 is a gene that helps metabolize copper, an element vital in regulating the amount of oxygen in the eye tissue. When SCO2 is not operating properly, oxygen levels can become too high and alter the development of a person's eye.

"This is the first time a gene mutation like this has been discovered," said Terri Young, M.D., an ophthalmology, pediatrics, and medicine professor at Duke. "It's one found in cases of inherited severe myopia among Caucasians where only one parent carries the gene for the condition and where the nearsightedness isn't associated with any other health conditions."

According to the study, SCO2 is a rare gene mutation and it is only believed to be one of many gene mutations to cause myopia, but the discovery of copper deficiency may help scientists further understand the disease.

"What we've found - and what's in pre-existing research - suggests that copper deficiencies could set people up to become nearsighted," Young said. "We didn't specifically test diets, but it's possible that mineral- and vitamin-deficient diets could play a role."

Young said she plans on adding SCO2 to a panel of studies associated with myopia rather than test for it alone. SCO2 is also known to affect other diseases, so further research is ongoing.