Congenital aniridia (AN) is a hereditary autosomal dominant developmental disorder of the eye. Heterozygous mutations in the PAX6 gene and chromosomal rearrangements involving the 11p13 locus lie behind the pathogenesis of the AN. The key role of the PAX6 gene in the regulation of embryogenesis and the pleiotropic effect of this transcription factor explain the damage of several tissues of the anterior and posterior segments of the eye, brain structures, and the disturbance of morphogenesis and endocrine function of the pancreas observed in AN. Recently AN has been considered a syndromic pathology by several researchers. The review suggests classification and summarizes information on the clinical characteristics and genetic basis of various forms of AN. The problem of discrimination of clinical-genetic variants of the dysgenesis of the anterior segment of the eye and the differential diagnosis of PAX6-associated AN with WAGR syndrome, anterior dysgenesis, other rare monogenic and chromosomal syndromes is discussed, and the role of molecular diagnostics is emphasized.

WAGRO syndrome is a rare genetic syndrome that includes Wilms tumor, aniridia, genitourinary system abnormalities, mental retardation, and obesity. The syndrome is associated with deletions of the short arm of chromosome 11 (11p), where the PAX6 and WT1 genes are located. We present the clinical case of a 7-year-old boy with aniridia, polar cataract, and concomitant neuromotor, psychomotor, and speech delays. Evaluation of the childs karyotype followed by confirmation using multiplex ligation-dependent probe amplification showed the presence of a deletion including in the 11p13-p14 region.