Congenital Abnormality
aniridia
[ a-nih-rih-dee-uh ]
Subclass of:
Eye Diseases, Hereditary;
Eye Abnormalities;
Iris Diseases
Definitions related to aniridia:
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A congenital abnormality in which there is only a rudimentary iris. This is due to the failure of the optic cup to grow. Aniridia also occurs in a hereditary form, usually autosomal dominant.NLM Medical Subject HeadingsU.S. National Library of Medicine, 2021
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A rare genetic inherited abnormality characterized by the partial or complete absence of the iris of the eye.NCI ThesaurusU.S. National Cancer Institute, 2021
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Abnormality of the iris characterized by, typically bilateral, complete or partial iris hypoplasia. The phenotype ranges from mild defects of anterior iris stroma only to almost complete absence of the iris.Human Phenotype Ontology (HPO)The Human Phenotype Ontology Project, 2021
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PAX6-related aniridia occurs either as an isolated ocular abnormality or as part of the Wilms tumor-aniridia-genital anomalies-retardation (WAGR) syndrome. Aniridia is a pan ocular disorder affecting the cornea, iris, intraocular pressure (resulting in glaucoma), lens (cataract and lens subluxation), fovea (foveal hypoplasia), and optic nerve (optic nerve coloboma and hypoplasia). Individuals with aniridia characteristically show nystagmus and impaired visual acuity (usually 20/100 - 20/200); however, milder forms of aniridia with subtle iris architecture changes, good vision, and normal foveal structure do occur. Other ocular involvement may include strabismus and occasionally microphthalmia. Although the severity of aniridia can vary between and within families, little variability is usually observed in the two eyes of an affected individual. WAGR syndrome. The risk for Wilms tumor is 42.5%-77%; of those who develop Wilms tumor, 90% do so by age four years and 98% by age seven years. Genital anomalies in males can include cryptorchidism and hypospadias (sometimes resulting in ambiguous genitalia), urethral strictures, ureteric abnormalities, and gonadoblastoma. While females typically have normal external genitalia, they may have uterine abnormalities and streak ovaries. Intellectual disability (defined as IQ <74) is observed in 70%; behavioral abnormalities include attention deficit hyperactivity disorder (ADHD), autism spectrum disorder, anxiety, depression...GeneReviewsUniversity of Washington, 2021
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Aniridia is a congenital, hereditary, bilateral, extreme form of iris hypoplasia that may be associated with other ocular defects. It describes an extreme form of iris hypoplasia in which the iris appears absent on superficial clinical examination.WebMD, 2019
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Aniridia is an eye disorder characterized by a complete or partial absence of the colored part of the eye (the iris) and is usually associated with foveal hypoplasia (underdevelopment of the part of the eye responsible for sharp central vision). This combination can lead to decreased visual acuity and involuntary eye movements...National Center for Advancing Translational Sciences
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