Vision problems are extremely common around the world, affecting literally billions of people. Now, investigators at the Purdue University are studying the eyes of zebrafish in order to figure out how our own vision functions. The studies could lead to new therapies for a wide array of conditions.
One of the most significant discoveries made to date is that of an enzyme that apparently plays a very important role in regulating the size of eyes in these fish. If a similar protein can be found in humans, then researchers could target it with next-generation drugs.
Some of the conditions that are caused by abnormalities in the size of eyes include nearsightedness (myopia) and farsightedness (hypermetropia). The former affects up to a third of children in the developed world, and around 80 percent of kids in poor countries.
Myopia is present in nearly a third of Earth's population, but only a fraction of these individuals wear glasses meant to address the sight error, or take other types of treatments. By eliminating the root cause of myopia – an excessive length of the eye – the need for glasses or surgery could simply disappear.
“New insights into the process of eye-size control in zebrafish may help our understanding of the regulation of eye size in humans,” Washington University neuroscience PhD student Zeran Li explains. She began the zebrafish study while a graduate student at the Purdue University.
“Vision problems occur when the size or shape of the eye changes, and what causes this is unclear. Perhaps this research will lead to a better understanding of this mechanism and the discovery of a new treatment for these problems,” she explains.
This class of eye size-related issues is called refractive errors, ophthalmologists say. They occur when the distance between the cornea and the retina is either smaller or larger than it should be. An incorrect distance means that the light is focused either before, or behind, the retina, not exactly on it.
Official statistics from the International Center for Eye Education indicate that 3.8 billion people around the world suffer from some type of refractive error. The new investigation therefore has the potential to improve the quality of life for the majority the Earth's population.
“The inspiration for this study came from the undergraduate students. Their observations and interpretations helped shape our current focus and allowed us to make this discovery. I'm very proud of the scientists they are becoming,” Purdue assistant professor of biological sciences, Yuk Fai Leung, says.
“Hopefully our efforts will expedite the discovery of novel treatments for human eye diseases,” the expert concludes.