Australian scientists say they have discovered why the human eye turns yellow with age.
The team found that, with advancing age, ultraviolet filters inside the eye break down and bind with neighbouring proteins, causing the eyes to yellow and diminishing their ability to distinguish shades of blue. The process is, they say, unique to human eyes. The discovery, reported in the American Journal of Biological Chemistry , opens the door to greater understanding of cataracts, Dr. Truscott said. The lenses of people with nuclear cataract go even darker, turning orange, brown and sometimes black. The discovery, made at the university-based Cataract Research Centre, may ultimately lead to the design of drugs to interfere with the body's manufacture of UV filters for the eyes.