What is Heterochromia Iridis by Alexandra Adelman

The iris is an intricate part of the eye. Its job is to level out the amount of light that enters the pupil, acting as an aperture. Iris can be many colors such as shades of brown, green, blue, hazel, and sometimes even violet. Heterochromia iridis is when the iris color does not match the other eye’s. The name is pretty self-evident; “hetero”, meaning different, “chrome-“, meaning color, and “iridis”, which refers to the colored part of one’s eye called the “iris”. In humans, this condition is not common but can be very noticeable. Someone may have two different colored eyes, such as one blue, and one brown. Other people may have a partially blue/brown iris in one eye, and the other a solid color of either blue or brown. These are just examples, as it can be present in any eye color.

Many factors cause Heterochromia iridis, whether it be an inherited trait or a disease, such as glaucoma or melanoma.  Some medications and eye drops related to the treatment of glaucoma have been reported to slightly change the patient’s eye color as well! A foreign body particle can cause damage to the eye, thus changing the iris by erupting blood vessels, etc. Other cases show that some congenital birth defects, such as Waardenburg Syndrome, Parry-Romberg Syndrome, and George-Weber Syndrome do support the cause for Heterochromia iridis. Many disabilities, including these syndromes, are accompanied by Heterochromia iridis. For example, studies have shown that there was a significant amount of children with Heterochromia iridis attending a School for the Deaf. This is partly due to a portion of the deaf population with Waardenburg Syndrome, which can result in both deafness and heterochromia. There are, however, cases where this condition does not merit any additional problems.

There are two main forms of heterochromia iridis in itself. Hypo-pigmentation and hyper-pigmentation. The differences are simple; hypo-pigmentation denotes that the iris affected is the lighter one of the two. On the other hand, hyper-pigmentation shows that the darker iris is the one that was ultimately different. Another type of heterochromia is “segmented heterochromia iridium”. “Iridium” is the singular version of iridis, meaning that the aforementioned condition only affects part of one of the iris’. For example, both eyes may be hazel but one of them may have a spot or section of brown coloring. This often goes unnoticed unless in bright lighting.

Other examples of heterochromia iridis are having the same general color eyes, but noticeably different shades. A person could have one iris hazel, while the other green, as with the famous actress Mila Kunis. In my case, my left iris is light brown, whereas my right iris is very dark brown, almost black. Because of signs of hyper-pigmentation, it is my right eye, the dark iris, that was affected. This condition only affects less than 200,000 people in the US. However, there are a few famous people who have it. The list includes actresses Mila Kunis and Kate Botsworth, as well as actors Dan Aykroyd, Simon Pegg, and Christopher Walken. Alexander the Great was documented to have two different colored eyes too. This condition is not necessarily symptomatic of a health issue, although many syndromes and problems include this abnormality. There is no cure for heterochromia iridis itself. There are, however, treatments if it is accompanied by a disease or health issue.

Works Cited

Bickford, Larry. “All About Eye Color.” Eye Color. EyeCare Reports, n.d. Web. 20 Jan. 2013.

Gladstone, Richard M., MD. “Development and Significance of Heterochromia of the Iris.” JAMA Network. American Medical Association, n.d. Web. 22 Jan. 2013.

“HETEROCHROMIA IRIDIS.” OMIM Entry 142500. John Hopkins University, n.d. Web. 22 Jan. 2013.

Rehman, Habib Ur, MBBS. “Heterochromia.” NCBI. U.S. National Library of Medicine, 26 Aug. 2008. Web. 20 Jan. 2013.

Visick, Spencer. “Famous People with Heterochromia Iridum.” IMDb. IMDb.com, 2010. Web. 22 Jan. 2013.