Congenital<unk> : inherited in autosomal dominant fashion (from men or women)<unk>  is classified primarily by onset: as either genetic or acquired. Although a distinction is frequently made between<unk>  that affects an eye completely or only partially (sectoral<unk> , it is often classified as either genetic (due to mosaicism or congenital) or acquired, with mention as to whether the affected iris or portion of the iris is darker or lighter. Most cases of<unk>  are hereditary, or caused by genetic factors such as chimerism, and are entirely benign and unconnected to any pathology, however, some are associated with certain diseases and syndromes. Sometimes one eye may change color following disease or injury. Genetic Abnormal iris darker *Lisch nodules – iris hamartomas seen in neurofibromatosis. *Ocular melanosis – a condition characterized by increased pigmentation of the uveal tract, episclera, and anterior chamber angle. *Oculodermal melanocytosis (nevus of Ota) *Pigment dispersion syndrome – a condition characterized by loss of pigmentation from the posterior iris surface which is disseminated intraocularly and deposited on various intraocular structures, including the anterior surface of the iris. *Sturge–Weber syndrome – a syndrome characterized by a port-wine stain nevus in the distribution of the trigeminal nerve, ipsilateral leptomeningeal angiomas with intracranial calcification and neurologic signs, and angioma of the choroid, often with secondary glaucoma. Abnormal iris lighter Waardenburg Syndrome Type II exhibiting complete<unk>  *Simple<unk>  – a rare condition characterized by the absence of other ocular or systemic problems. The lighter eye is typically regarded as the affected eye as it usually shows iris hypoplasia. It may affect an iris completely or only partially. *Congenital Horner's syndrome – sometimes inherited, although usually acquired. *Waardenburg syndrome – a syndrome in which<unk>  is expressed as a bilateral iris hypochromia in some cases. A Japanese review of 11 children with albinism found that the condition was present. All had sectoral/partial<unk> . *Piebaldism – similar to Waardenburg's syndrome, a rare disorder of melanocyte development characterized by a white forelock and multiple symmetrical hypopigmented or depigmented macules. *Hirschsprung's disease – a bowel disorder associated with<unk>  in the form of a sector hypochromia. The affected sectors have been shown to have reduced numbers of melanocytes and decreased stromal pigmentation. *Incontinentia pigmenti *Parry–Romberg syndrome Acquired An Alaskan husky sled dog with<unk> . Huskies are a breed known to have a high incidence of<unk> . Acquired<unk>  is usually due to injury, inflammation, the use of certain eyedrops that damage the iris, or tumors. Abnormal iris darker *Deposition of material *Siderosis – iron deposition within ocular tissues due to a penetrating injury and a retained iron-containing, intraocular foreign body. *Hemosiderosis – long standing hyphema (blood in the anterior chamber) following blunt trauma to the eye may lead to iron deposition from blood products. *Certain eyedrops – prostaglandin analogues (latanoprost, isopropyl unoprostone, travoprost, and bimatoprost) are used topically to lower intraocular pressure in glaucoma patients. A concentric<unk>  has developed in some patients applying these drugs. A stimulation of melanin synthesis within iris melanocytes has been postulated. *Neoplasm – Nevi and melanomatous tumors. *Iridocorneal endothelium syndrome *Iris ectropion syndrome Abnormal iris lighter *Fuchs<unk>  iridocyclitis – a condition characterized by a low grade, asymptomatic uveitis in which the iris in the affected eye becomes hypochromic and has a washed-out, somewhat moth eaten appearance. The<unk>  can be very subtle, especially in patients with lighter colored irides. It is often most easily seen in daylight. The prevalence of<unk>  associated with Fuchs has been estimated in various studies with results suggesting that there is more difficulty recognizing iris color changes in dark-eyed individuals. *Acquired Horner's syndrome – usually acquired, as in neuroblastoma, although sometimes inherited. *Neoplasm – Melanomas can also be very lightly pigmented, and a lighter colored iris may be a rare manifestation of metastatic disease to the eye. *Parry–Romberg syndrome – due to tissue loss.<unk>  has also been observed in those with Duane syndrome. *Chronic iritis *Juvenile xanthogranuloma *Leukemia and lymphoma Partial<unk>  – different colors in the same iris Partial<unk>  is most often a benign trait of genetic origins, but, like complete<unk> , can be acquired or be related to clinical syndromes. Sectoral<unk>  Sectoral In sectoral<unk> , areas of the same iris contain two different colors, the contrasting colors being demarcated in a radial, or sectoral, manner. Sectoral<unk>  may affect one or both eyes. It is unknown how rare sectoral<unk>  is in humans, but it is considered to be less common than complete<unk> . Central Human eye with pronounced central<unk>  Central<unk>  is also an eye condition where there are two colors in the same iris; but the arrangement is concentric, rather than sectoral. The central (pupillary) zone of the iris is a different color than the mid-peripheral (ciliary) zone. Central<unk>  is more noticeable in irises containing low amounts of melanin.
Heterochromia iridum
Spotted lunulae
Pili multigemini
Aniridia
Macrodontia 
Hippocratic facies
Cryptotia
Conduplicato corpore