FOXC1 and Axenfeld-Rieger syndrome: DNA mutations involving PITX2, located at 4q25 [36], result in ARS in which patients have ocular phenotypes often seen with craniofacial and dental abnormalities, while mutations in FOXC1 located at 6p25 result in ARS defined by ocular phenotypes observed with cardiovascular defects and sensorineural hearing loss.