While more and more frequently mutations of the FKHL7 gene located at 6p25 is reported in the association ARS [40–43], also some sporadic cases of ARS have been related to deletion of the PAX6 gene (still controversial and to be definitively demonstrated [44]) at 11p13 and deletion of the 16q23-q24 region; a second locus for Rieger syndrome located on chromosome 13q14 has also recently been identified [45]. The gene discussed is PAX6; the disease is Axenfeld-Rieger syndrome.