NATIONAL DIFFERENT COLORED EYES DAY
National Different Colored Eyes Day is observed annually on July 12th. There are many people out there that have two different colored eyes, and this is their day to celebrate!
Having two different colored eyes is a condition called Heterochromia. There are three types of Heterochromia:
Complete heterochromia – one iris is a different color from the other.
Partial heterochromia or sectoral heterochromia – part of one iris is a different color from the rest of the iris.
Central heterochromia – an inner ring is a different color than the rest of the iris.
The concentration and distribution of melanin are what determines the eye color, specifically the color of the irises. The affected eye may be hyperpigmented (hyperchromic) or hypopigmented (hypochromic). The excess of melanin indicates hyperplasia of the iris tissues, whereas a lack of melanin indicate hypoplasia.
Most cases of heterochromia are hereditary, caused by a disease or syndrome or due to an injury. It is possible that just one eye may change color following certain diseases or injuries.
A few celebrities are known to have two different colored eyes include David Bowie, Christopher Walken, Dan Aykroyd, Jane Seymour and Mila Kunis.