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International Birth Defects Information Systems
Aniridia Syndrome

International Birth Defects Information Systems



Aniridia Syndrome


Topics: | Aniridia Syndrome | An2 Paired Box Homeotic Gene; PAX6 |
Gillespie S. |

Related Topics: | 11p Chromosome | Eye / Ocular | WAGR S. | Wilms Tumor |

Service Related: | Support Groups | Professional Associations | Key Information Sources |

Languages: | English | Spanish |

106210 ANIRIDIA, TYPE II
Victor A. McKusick, OMIM, Johns Hopkins University, August 13, 2007
Visitor Comments [for Professionals mainly]
Alternative titles; symbols
AN2 PAIRED BOX HOMEOTIC GENE 6; PAX6
.. At least 2 distinct types of aniridia were thought to exist on the basis of linkage differences and possibly phenotypic differences. The designation AN1 was used for the aniridia locus thought to be on chromosome 2 and AN2 for the locus on chromosome 11. However, Lyons et al. (1992) ... Excluded linkage to markers in the terminal portion of 2p; contrariwise, strong indication of linkage to markers in the 11p13 region was found ... Entitled aniridia, this disorder is a panocular one taking its name from the noticeable iris hypoplasia seen in most cases ... In the Gillespie syndrome (206700), aniridia is associated with cerebellar ataxia and mental retardation ... A third of all cases of aniridia are sporadic and these are often found to have cytogenetically detectable deletions involving 11p13, which, if extensive enough, cause the WAGR contiguous gene syndrome ... Moore et al. (1986) concluded that single breaks are associated with isolated aniridia whereas deletion of 11p13 results in the WAGR syndrome ...

Aniridia factsheet
RNIB - Royal National Institute for the Blind, May 17, 2007
Visitor Comments [Support Groups]
Aniridia is a rare congenital defect causing incomplete formation of the iris. This can cause loss of vision, usually affecting both eyes. In Aniridia, although not entirely absent, all that remains of the iris is a thick collar of tissue around its outer edge and the muscles which open and close the pupil are entirely missing. The appearance of a "black iris" is the result of the really enormous pupil ...
There is no single cause ... Falls roughly into two groups, one of which is hereditary and the other of unknown origin ...
Aniridia can result from autosomal dominant or autosomal recessive inheritance or may occur on its own. Autosomal dominant individuals in this group will be unlikely to have additional health or developmental problems ... Autosomal recessive inheritance carries a risk of accompanying mental handicap ...
Rarely Aniridia may be associated with a Wilms' tumour of the kidney ...

ANIRIDIA; AN1
Victor A. McKusick, OMIM, Johns Hopkins University, December 23, 2002
... A form of aniridia is not linked to markers on 2p as previously thought, ... There probably is no form of autosomal dominant aniridia other than that which maps to 11p13 and was designated AN2 ...
Shaw et al. (1960) ascertained 176 cases of aniridia in the lower Michigan peninsula ... mutation rate about 4 x 10(-6) per gamete per generation. Affected persons may be visually handicapped because of nystagmus, cataract or glaucoma ... Undoubtedly more than one "cause" of aniridia exists ... Gove et al. (1961) identified 77 cases of aniridia descended from an affected woman born in 1824 ... Delleman and Winkelman (1973) emphasized that atypical colobomata and slitlike defects of the iris stroma may be partial expressions of aniridia ... a fourth type associated with Wilms tumor, genital abnormalities, and deletion of 11p13 ( WAGR syndrome ) ...

PAIRED BOX GENE 6; PAX6
Victor A. McKusick, OMIM, Johns Hopkins University, August 13, 2007
CLINICAL SYNOPSIS
Aniridia
Decreased vision
Cataract
Glaucoma
Nystagmus
Atypical colobomata
Slitlike iris stromal defects
Corneal pannus
Foveal hypoplasia
Optic nerve hypoplasia
Thinned iris
Inheritance:
Autosomal dominant
Alternative titles; symbols
ANIRIDIA, TYPE II, INCLUDED; AN2, INCLUDED
Gene Map Locus: 11p13
As indicated in 106200, at least 2 distinct types of aniridia were thought to exist on the basis of linkage differences and possibly phenotypic differences ... AN1 was used for the aniridia locus thought to be on chromosome 2 and AN2 for the locus on chromosome 11. However, Lyons et al. (1992) restudied the family on which mapping of an aniridia locus to 2p was based (Ferrell et al., 1980). They excluded linkage to markers in the terminal portion of 2p; ... ... this disorder is a panocular one taking its name from the noticeable iris hypoplasia seen in most cases ...
Approximately 92 % or reported mutations of PAX6 in aniridia patients lead to premature truncation of the protein, i.e., are nonsense, splicing, insertion, and deletion mutations, ... ... "missing" PAX6 missense mutations underlie phenotypes distinct from classical aniridia ...

ANIRIDIA, CEREBELLAR ATAXIA, AND MENTAL DEFICIENCY
Victor A. McKusick, OMIM, Johns Hopkins University, March 17, 2004
Alternative titles; symbols
GILLESPIE SYNDROME
Gillespie (1965) described brothers and sisters with this combination which had apparently not been reported previously, although cerebellar ataxia mental deficiency and congenital cataracts are known in the Marinesco - Sjogren syndrome. It is likely that Gillespie's patients represent a separate mutation ... Sarsfield (1971) reported a further example ... Bilateral partial aniridia was noted at birth and developmental milestones were subsequently delayed ... Muscle biopsies and nerve conduction times were normal, there was persistent hypotonia ... Attention tremor, and scanning speech ... Mental retardation was evident ... Lens and cornea of Gillespie syndrome are clear ...

ANIRIDIA AND ABSENT PATELLA
Victor A. McKusick, OMIM, Johns Hopkins University, March 11, 1994
Mirkinson and Mirkinson (1975) reported this combination in a boy, his father, and his paternal grandmother ... bilateral cataracts and glaucoma complicated the aniridia. The patella was either hypoplastic or aplastic ...

ANIRIDIA, PARTIAL, WITH UNILATERAL RENAL AGENESIS AND PSYCHOMOTOR RETARDATION
Victor A. McKusick, OMIM, Johns Hopkins University, November 12, 1995
Sommer et al. (1974) reported a brother and sister with this syndrome ... congenital glaucoma, telecanthus and frontal bossing as well ...

ANIRIDIA, MICROCORNEA, AND SPONTANEOUSLY REABSORBED CATARACT
Victor A. McKusick, OMIM, Johns Hopkins University, March 11, 1994
Yamamoto et al. (1988) observed this combination in 3 generations of a family and possibly in a fourth ...

Aniridia
Nobelprize.org, 1995
If the homeotic gene PAX6 is mutated the result is a child born with complete loss of the iris ... Experimental studies in mice have shown that disturbances in homeotic genes can cause a malformation of the colon called megacolon ...

ANIRIDIA
Texas School for the Blind and Visually Impaired
Rare, congenital absence or partial absence of the iris; genetically caused by an autosomal dominant or recessive hereditary pattern. Often, the iris is vestigal (little or more than margin is present) and the eye appears to have no color (only a larger than normal pupil) Other deformities of ... (... cataract) glaucoma .... photophobia ... nystagmus, cataracts, displaced lens, ... underdeveloped retina ...
TREATMENT: Pinhole contact lenses; tinted lenses ... sunglasses ...

Tumor de Wilms y otros tumores renales infantiles: Tratamiento (PDQ®)
National Cancer Institute, January 4, 2008
Visitor Comments [for Professionals mainly] [Spanish]
Información general ... Este sumario informativo sobre el tratamiento del cáncer provee un compendio que abarca tanto el pronóstico y diagnóstico como la clasificación y tratamiento del tumor de Wilms y otros tumores renales infantiles (sarcoma de células claras del riñón, tumor rabdoide del riñón, tumor neuroepitelial del riñón, nefroblastoma cístico parcialmente diferenciado, nefroma mesoblástico y carcinoma de células renales).

Aniridia congénita
Gonzalo Carracedo O.D., Gaceta Optica
Visitor Comments [Spanish]
La aniridia, falta total o parcial del iris, se define como una alteración congénita que afecta al desarrollo del ojo. Se produce por mutaciones en el gen PAX6, gen responsable del desarrollo del ojo, tejido nasal y cerebro. Es una afectación bilateral que además de ausencia del iris también se caracteriza por presentar signos en otras estructuras oculares, como la córnea, el cristalino y la retina. Sus síntomas principales son la fotofobia y la baja AV. No existe un tratamiento global para la aniridia, se trata cada signo por separado. Las investigaciones actuales van dirigidas en dos sentidos: mejorar la calidad de vida de los pacientes anirídicos con nuevos fármacos y buscar la solución para dicha patología dentro del campo de la genética ...

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Last Updated: 2008/3/6

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American Medical Association