PAX6 and aniridia: Due to the high complexity of the genetic mechanisms involved in congenital aniridia and related syndromes, clinical testing is currently performed by combining different molecular and cytogenetic approaches, such as Sanger sequencing for screening of intragenic PAX6 mutations, Multiplex Ligation-dependent Probe Amplification (MLPA) and/or Fluorescence In Situ Hybridization(FISH) for analysis of small interstitial 11p13 microdeletions, and conventional or high resolution karyotyping for other microscopic 11p13 rearrangements [6, 14–16].