Abstract
Purpose :
Anterior segment dysgenesis refers to a wide range of heterogeneous disorders involving ocular and systemic malformations, among which the Axenfeld-Rieger syndrome (ARS) is the most common syndrome. In the majority of cases, ARS is caused by mutations in one of three genes, PAX6, FOXC1, and PITX2, which are inherited in an autosomal dominant manner. The main object of our study was to further examine these genes in order to identify possible novel mutations in Pakistani and Mexican families affected by the ARS phenotype.
Methods :
A total of 21 (n=16 Pakistani, n=5 Mexican) probands with a diagnosis of ARS were recruited for this study. Genomic DNA was isolated from peripheral blood of the probands and their unaffected family members. For the analysis of the coding exons and the flanking intronic regions of the PITX2 gene, Polymerase Chain Reaction and Sanger sequencing were used.
Results :
We identified three novel heterozygous mutations in the PITX2 gene, segregating with the ARS phenotype within the families. Two novel mutations, c.226G>T, p.(Ala76Ser) and c.455G>A, p.(Cys152Tyr), were identified in two Pakistani families, and one, c.242_265del, p.(Lys81_Gln88del), was found to segregate in a Mexican family.
Conclusions :
Our study extends the range of PITX2 mutations in individuals with ARS, enabling an improved diagnosis of this rare but serious syndrome.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.