Heterochromia iridis is a condition in which the iris, the colored part of the eye, is composed of different colored patches or segments, or when the iris of one eye is a different color than the iris of the other eye. This condition may involve one or both eyes. Most cases of heterochromia iridis occur by chance and are not associated with any other symptoms or problems. In some cases, heterochromia iridis may be present from birth as part of a genetic disorder, such as Waardenburg syndrome, Sturge-Weber syndrome, or Parry-Romberg syndrome. In other cases, this condition may be acquired if eye color changes after an injury to the eye, due to damage to nerves near the eyes, or in response to an environmental exposure. Source: Genetic and Rare Diseases Information Center (GARD), supported by ORDR-NCATS and NHGRI.