Myopia studied as a health concern

It’s easy for many of us to correct nearsightedness — we go to the eye doctor, pick out a pair of glasses or fill a prescription for contact lenses, and voilà, we greatly improved vision. Thus, nearsightedness, also known as myopia, is something that we may not consider much as a public health concern. However, researchers at Hopkins and across the world believe there to be a better treatment for this prevalent condition that can be derived through genomic studying.

“I think people tend to dismiss myopia a little bit in terms of its public health significance. Because, frankly, you can get a pair of glasses and see well, and most of the time myopia is correctable. But it is important to understand why myopia is the leading cause of visual impairment,” Robert Wojciechowski, an assistant professor of epidemiology at the School of Public Health, said.

Wojciechowski, with other researchers, applied his interest in genetic epidemiology of eye disease and eye disorders and came much closer to discovering the cause for the prevalence of myopia. They managed to determine 24 new genes that contribute to the development of myopia.

“It is the largest study conducted to date, and by far we have discovered more about the genetics of myopia in human population than the previous centuries of research,” Wojciechowski said. “We discovered 24 new genes, and before this study there had been only two genes that had been confirmed, so we’re considering this very significant.”

This international collaboration included 32 studies, 27 Caucasian and 5 Asian populations, with a total of 420,000 people. The participants’ DNA markers were correlated with refractive error, the power of glasses needed to correct vision problems.

“The amount of data you have to put together is a challenge in and of itself. That’s starting to become somewhat of a factor that is limiting, and it takes a lot to analyze the data. So I think that the biggest challenge is being inundated with data,” Wojciechowski said.

While genetic makeup plays a part in the development of myopia, so do environmental factors. In fact, one of the goals behind the research is to distinguish the contribution of genetic factors from environmental ones. A major factor in Asia that leads to myopia is urbanization, because people in urban areas develop myopia more than those in rural areas.

“There is a host of environmental exposures that we know have an effect on myopia but how they interact with the genes is still unknown, so the next step is to find out how these genes and the environment interact with one another.  We really have to incorporate environmental factors into our analyses to see how they interact with genes to better understand the development of myopia,” Wojciechowski said.

Researchers estimate that 2.5 billion people will have myopia by 2020, many of whom will lack access to or have the means for purchasing proper prescription. Myopia rates are expected to increase with the advent of technology, like cell phones, that require users to focus at short distances. Unfortunately, treatments for myopia do not look promising.

“There have been various treatments that have been tried, none of them have been particularly successful, and in some cases the side effects are actually worse than having myopia,” Wojciechowski said.  However, there is hope in acquiring habits that promote eye health.

“I would recommend taking periodic breaks from reading; if you read for an hour or spend an hour on the computer screen, take a five or ten minute break to look outside and focus on something far away. People are not going to stop texting or reading or using their electronic devices, but I think it is important to take breaks every once in a while.”

Thanks to the work of Wojciechowski and his colleagues, the understanding of the myopia’s causes is becoming clearer, and more treatments that attack the true roots of the condition may be available in the future.