title: [Molecular exploration of the R91W (RPE65 gene) in Tunisian patients with early onset retinal dystrophy and early onset retinitis pigmentosa].
abstract: BACKGROUND
  Inherited retinal dystrophies are the major causes of blindness and visual impairment. Visual loss is due to neurosensory retinal and pigment epithelium cells degeneration. The most severe were Leber Congenital amaurosis (LCA), juvenile retinitis pigmentosa (RP) and early onset RP. The LCA and juvenile RP are called «Early Onset Retinal Dystrophy» (EORD).
  
  
  OBJECTIVE
  Molecular exploration of the R91W (RPE65 gene) in Tunisian patients with Early Onset Retinal Dystrophy and early onset RP.
  
  
  METHODS
  All patients underwent a complete ophthalmological and a general examinations. The R91W exploration was performed by direct sequencing of exon 4 of the RPE65 gene and enzyme digestion.
  
  
  RESULTS
  Among 47 patients, 13 were from Nabeul. Twenty three had an EROD with a visual loss under the age of 2 years. Twenty four were with early onset RP and had these symptoms between the ages of 4 and 10 years. The best corrected visual acuity ranged from 2/10 to 1/60. Among the explored 94 chromosomes, the R91W (325C>T) allele was identified in heterozygous state in a sibling from Nabeul. The allele frequency was 2.12% (2/94).
  
  
  CONCLUSIONS
  All our patients had severe forms of RP with a decrease in visual acuity and a wide advanced retinal degeneration. The R91W mutation (325C>T) was not the major cause of EORD and early onset RP among Tunisian patients.
authors.forename: Ibtissem
authors.initials: I
authors.lastname: Chouchene
authors.forename: Leila
authors.initials: L
authors.lastname: Largueche
authors.forename: Kaouther
authors.initials: K
authors.lastname: Derouiche
authors.forename: Souad
authors.initials: S
authors.lastname: Mabrouk
authors.forename: Sonia
authors.initials: S
authors.lastname: Abdelhak
authors.forename: Leila
authors.initials: L
authors.lastname: El Matri
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D015785:Eye Diseases, Hereditary / Q000235:genetics*; D005260:Female; D005787:Gene Frequency; D006801:Humans; D008297:Male; D008875:Middle Aged; D009154:Mutation; D058499:Retinal Dystrophies / Q000235:genetics*; D012174:Retinitis Pigmentosa / Q000235:genetics*; D014416:Tunisia; D055815:Young Adult; D019745:cis-trans-Isomerases / Q000235:genetics*; D000099178:Retinoid Isomerohydrolase
chemical_list: D019745:cis-trans-Isomerases; D000099178:Retinoid Isomerohydrolase