Aniridia 3

Clinical Characteristics
Ocular Features: 

One 4-generation Chinese family with 8 affected members has been reported. Complete bilateral iris defects were seen all patients who by 10 years of age also had cataracts.  No corneal opacities were seen.  Two patients were diagnosed with glaucoma.  No fundus abnormalities were reported.

Systemic Features: 

No systemic abnormalities have been reported. 

Genetics

Hereditary aniridia results from a dysfunction of the regulatory gene PAX6.  In aniridia 1 (106210) the PAX6 gene (a transcription regulator) gene itself contains mutations.  In anirdia 2 (617141) the mutation occurs in the ELP4 gene, whose product is a cis-regulatory enhancer of PAX6. 

Aniridia 3 results from heterozygous mutations in the TRIM44 gene (11p13).  The TRIM44 gene is a negative regulator which normally suppresses the expression of PAX6 and the reported missense mutation (p.G155R) enhances its activity.

Treatment
Treatment Options: 

Surgical removal of cataracts and glaucoma treatment may be of benefit.

References