title: Absence of PITX3 mutation in a Tunisian family with congenital cataract and mental retardation.
abstract: OBJECTIVE
  The PITX3 (pituitary homeobox 3) gene encodes for a homeobox bicoid-like transcription factor. When one allele is mutated, it leads to dominant cataract and anterior segment mesenchymal dysgenesis in humans. When both copies are mutated, homozygous mutation contributes to microphtalmia with brain malformations. In the current study, a family with autosomal recessive congenital cataract (ARCC) associated with mental retardation (MR) was examined to identify PITX3 mutations.
  
  
  METHODS
  Sequencing of the PITX3 gene was performed on two affected and three unaffected members of the studied Tunisian family. The results were analyzed with Sequencing Analysis 5.2 and SeqScape.
  
  
  RESULTS
  No mutation in the four exons of PITX3 was revealed. Two substitution polymorphisms, c.439C>T and c.930C>A, were detected in exons 3 and 4, respectively. These alterations did not segregate with the disease.
  
  
  CONCLUSIONS
  Although PITX3 was shown to be essential to normal embryonic eye and brain development in vertebrates, we report the absence of PITX3 mutations in a family presenting congenital cataract and mental retardation.
authors.affiliation: Faculté de Médecine de Tunis, Laboratoire Génétique Humaine, Tunis, Tunisia.
authors.forename: Manèl
authors.initials: M
authors.lastname: Chograni
authors.forename: Myriam
authors.initials: M
authors.lastname: Chaabouni
authors.forename: Imen
authors.initials: I
authors.lastname: Chelly
authors.forename: Mohamed Bechir
authors.initials: MB
authors.lastname: Helayem
authors.forename: Habiba
authors.initials: H
authors.lastname: Chaabouni-Bouhamed
mesh_terms: D000293:Adolescent; D000328:Adult; D002386:Cataract / Q000150:complications / Q000151:congenital* / Q000235:genetics*; D002648:Child; D002675:Child, Preschool; D005190:Family; D005260:Female; D018398:Homeodomain Proteins / Q000235:genetics*; D006801:Humans; D008607:Intellectual Disability / Q000150:complications* / Q000235:genetics*; D008297:Male; D009154:Mutation / Q000235:genetics*; D010375:Pedigree; D014157:Transcription Factors / Q000235:genetics*; D014416:Tunisia; D055815:Young Adult
chemical_list: D018398:Homeodomain Proteins; D014157:Transcription Factors; C433629:homeobox protein PITX3