PITX2 and Axenfeld-Rieger syndrome: In light of recurrent non-coding deletions at the PITX2 locus, the haploinsufficient nature of PITX2-associated ARS, and the highly specific phenotype observed here, the most likely consequence of the Family 2 inversion appears to be a loss of PITX2 expression due to the displacement of the PITX2 gene body from its enhancer loci.