What is Aniridia?
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Aniridia
by definitional terms means
congenital
absence or partial absence of the
iris.
However this is not the only feature of Aniridia, as will be discussed
later.
Aniridia is rare. Its incidence is between 1/50,000 and 1/100,000. The
genetic defect has been found to be a deletion on chromosome 11. It is
an
autosomal dominant
condition in 2/3 of the cases. Approximately, a third of all cases of
Aniridia are
sporadic
and these are often found to have
cytogentically detectable
deletions involving 11p13, which, if extensive enough, cause the
WAGR contiguous gene syndrome
.
As stated above, Aniridia is more than just being born without an Iris.
Many aniridics have developmental and ocular abnormalities and may exhibit
the presence of one or more of these associated ocular abnormalities:
all of which contribute to severe reduction in visual acuity.
For more detailed information on the subject of Aniridia, its associated
conditions, and new research, please go to the Members' Area. If not
currently a member, please register now so you can get the full benefit
of the Aniridia Foundation Internationals resources.