The previously reported patients from family 4 [9] and family 5 [21] have classic ARS and harbor an A>G mutation 11 nt upstream of the 3' ss associated with PITX2 exon 5 (mutation IVS5-11A>G) (g.20745A>G as seen in PITX2 sequence GenBank # AF238048; Figure 2C). Here, PITX2 is linked to Axenfeld-Rieger syndrome.