Eye color is a genetic trait determined primarily by the amount and type of pigments present in the iris. There are three true colors in eyes—brown, yellow, and gray—that combine to produce a number of hues. Variations in color are attributed to varying ratios of melanin. Of the major eye colors, brown is the most common, followed by blue. The rarest, green, is possessed by just two percent of the human population. What condition can cause a person to have two different eye colors? Discuss
Source: The Free Dictionary