PAX6 and isolated aniridia: For example, in a patient with the highly specific phenotype aniridia (AN1; OMIM: #106210; typically caused by a haploinsufficiency of PAX6) but with negative clinical genetic tests, a de novo SNV was identified in an ultra-conserved cis-element (SIMO enhancer) located 150 kb downstream from PAX6 [26] (Table 1).