the PAX6 gene. Some mutations appear to inhibit gene function more than others, with subsequent variability in the severity of the disease. Thus, some aniridic individuals are only missing a relatively small amount of iris, do not have foveal hypoplasia, and retain relatively normal vision. Presumably, the genetic defect in these individuals causes less "heterozygous insufficiency," meaning they retain enough gene function to yield a milder phenotype. AN Aniridia and absent patella Aniridia, microcornea, and spontaneously reabsorbed cataract Aniridia, cerebellar ataxia, and mental deficiency (Gillespie syndrome) Mutational analysis Molecular (DNA) testing for PAX6 gene mutations (by sequencing of the entire coding region and deletion/duplication analysis) is available for isolated aniridia and the Gillespie syndrome. For the WAGR syndrome, high-resolution cytogenetic analysis and fluorescence in situ hybridization (FISH) can be utilized to identify deletions within chromosome band 11p13, where both the PAX6 and WT1 genes are located. Symptoms Aniridia can cause many symptoms, such as: Poor vision (not always present) More sensitivity to light Fast, uncontrolled, shaking "to and from" eye movements (nystagmus) Eyes don't line up (strabismus) Treatment In May 2018, the U.S. Food and Drug Administration approved the CustomFlex Artificial Iris, the first synthetic iris for use in adults and children with congenital aniridia or iris defects related to other conditions, such as albinism, traumatic injury, or surgical removal due to ocular melanoma. The artificial iris is a surgically implanted device made of thin, foldable, medical-grade silicone and is custom-sized and colored for each individual patient. The prosthetic iris is held in place by the anatomical structures of the eye or, if needed, by sutures. See also WAGR syndrome Scleral lenses References External links GeneReviews/NCBI/NIH/UW entry on Aniridia NCBI/Molecular diagnosis of aniridia OMIM entries on Aniridia GeneReviews/NIH/NCBI/UW entry on Wilms Tumor Overview Genetics Congenital disorders of eyes