Purpose: Rieger syndrome is an autosomal dominant condition defined by anterior segment dysgenesis in combination with facial, dental, skeletal and umbilical abnormalities. To date Rieger syndrome has been associated with mutations in the PITX2 gene at chromosome 4q25 and a second locus has been found at chromosome 13q14.
Methods: We describe a Rieger syndrome case with all the typical dysmorphic features and the molecular genetic finding by use of FISH analysis of the PAX6 gene.
Results: An eight-year-old girl had iris stroma hypoplasia, corectopia and iridogoniodysgenesis. She had an underdeveloped premaxilla and a congenital absence of nine teeth in the maxilla. The front teeth in the mandible were peg-shaped and all teeth were small. There was failure of involution of the periumbilical skin. FISH analysis using probes for the PAX6 gene showed a small deletion for the PAX6 gene on one homologue of chromosome 11.
Conclusion: Rieger syndrome can -- in addition to PITX2 gene mutations and abnormalities at chromosome 13q14 -- be associated with PAX6 gene abnormalities.