Eye Anterior Segment Abnormalities
Region: PITX2 upstream regulatory regionPITX2 upstream regulatory region
PITX2 encodes a homeodomain containing transcription factor.
There have been over 5 affected individuals across a number of publications with deletions in an agenic region approx 150kb upstream of PITX2 presenting with an Axenfeld Rieger phenotype.
There have also been reports of individuals with balanced translocations transecting the region on 4p with a similar phenotype.
Functional studies have interrogated this region identifying 11 conserved elements that are thought to represent enhancers. Zebrafish studies were performed by Volkmann et al with varying sized deletions in the region showing an effect on PITX2 gene expression.
Protas et al used a zebrafish model modified by CRISPR/Cas9 to delete an orthologous region similar to that seen in an affected individual. This resulted in recapitulation of the phenotype.
Note coordinates may not be precise (smaller deletions have been reported to cause disease).
Sources: LiteratureCreated: 19 Feb 2026, 12:13 p.m.
Mode of inheritance
MONOALLELIC, autosomal or pseudoautosomal, NOT imprinted
Phenotypes
Axenfeld-Rieger syndrome, MONDO:0019187
Publications
Region: PITX2 upstream regulatory region was added Region: PITX2 upstream regulatory region was added to Eye Anterior Segment Abnormalities. Sources: Literature SV/CNV tags were added to Region: PITX2 upstream regulatory region. Mode of inheritance for Region: PITX2 upstream regulatory region was set to MONOALLELIC, autosomal or pseudoautosomal, NOT imprinted Publications for Region: PITX2 upstream regulatory region were set to PMID: 20881290, 28911203, 14991915, 9480756 Phenotypes for Region: PITX2 upstream regulatory region were set to Axenfeld-Rieger syndrome, MONDO:0019187