Ever seen someone with two eyeballs that have different colors? Surely it happened naturally, not due to the use of colored contact lenses. In the medical world, the difference is known as Heterochromia Iridum.
Why the color of eyeballs different? The answer is because Heterochromia Iridum is abnormalities in the iris of the eye. This disorder usually consists of two eyeballs that have different colors. For example, the left eyeball which has a dark color while the right eye has a bright color. Even some that cause the eyeball to have some color variation.
The color of the iris usually varies from light brown, dark blue to black. Eye color that varies is usually determined by the amount of melanin, which is a brown pigment found in the eye, called the iris. If the eyes are blue, this is caused by at least the amount of melanin, but if the eye is brown, it means the amount of melanin contained a lot.
People with hair color and skin darker have more melanin, so their eyes are brown, while the color of the hair and skin paler have less melanin amount so that their eyes are usually lighter-coloured.
Although unique, disorders that are usually found in animals such as horses, cats, dogs and some species are harmless. But it turns out humans may also have this disorder.
The cause of the abnormality of the iris can be due to heredity, trauma, or because the treatment that can increase or reduce the pigmentation on one of the iris. Some public figures who have eye disorders Heterochromia Iridum are Kate Bosworth, Mila Kunis, Max Scherzer, Michael Schwimer and Simon Pegg.