Expanding the Phenotypic Spectrum of PAX6 Mutations: From Congenital Cataracts to Nystagmus

Genes (Basel). 2021 May 9;12(5):707. doi: 10.3390/genes12050707.

Abstract

Background: Congenital aniridia is a complex ocular disorder, usually associated with severe visual impairment, generally caused by mutations on the PAX6 gene. The clinical phenotype of PAX6 mutations is highly variable, making the genotype-phenotype correlations difficult to establish.

Methods: we describe the phenotype of eight patients from seven unrelated families with confirmed mutations in PAX6, and very different clinical manifestations.

Results: Only two patients had the classical aniridia phenotype while the other two presented with aniridia-related manifestations, such as aniridia-related keratopathy or partial aniridia. Congenital cataracts were the main manifestation in three of the patients in this series. All the patients had nystagmus and low visual acuity.

Conclusions: The diagnosis of mild forms of aniridia is challenging, but these patients have a potentially blinding hereditary disease that might present with a more severe phenotype in future generations. Clinicians should be aware of the mild aniridia phenotype and request genetic testing to perform an accurate diagnosis.

Keywords: PAX6; aniridia; congenital cataracts; nystagmus.

Publication types

  • Case Reports
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Aniridia / genetics*
  • Aniridia / pathology
  • Cataract / genetics*
  • Cataract / pathology
  • Child
  • Corneal Dystrophies, Hereditary / genetics*
  • Corneal Dystrophies, Hereditary / pathology
  • Female
  • Humans
  • Infant
  • Infant, Newborn
  • Male
  • Mutation
  • Nystagmus, Congenital / genetics*
  • Nystagmus, Congenital / pathology
  • PAX6 Transcription Factor / genetics*
  • Phenotype*

Substances

  • PAX6 Transcription Factor
  • PAX6 protein, human