Novel BEST1 gene mutations associated with two different forms of macular dystrophy in Tunisian families

Clin Exp Ophthalmol. 2019 Nov;47(8):1063-1073. doi: 10.1111/ceo.13577. Epub 2019 Jul 24.


Background: Epidemiological studies of hereditary eye diseases allowed us to identify two Tunisian families suffering from macular dystrophies: Best vitelliform macular dystrophy (BVMD) and autosomal recessive bestrophinopathy (ARB). The purpose of the current study was to investigate the clinical characteristics and the underlying genetics of these two forms of macular dystrophy.

Methods: Complete ophthalmic examination was performed including optical coherence tomography, electroretinography, electrooculography and autofluoresence imaging in all patients. Genomic DNA was extracted from peripheral blood collected from patients and family members.

Results: Sanger sequencing of all exons of the BEST1 gene in both families identified two new mutations: a missense mutation c.C91A [p.L31 M] at the N-terminal transmembrane domain within the ARB family and a nonsense mutation C1550G (p.S517X) in the C-terminal domain segregating in the BVMD family.

Conclusions: Several mutations of the BEST1 gene have been reported which are responsible for numerous ocular pathologies. To the best of our knowledge, it is the first time we report mutations in this gene in Tunisian families presenting different forms of macular dystrophy. Our report also expands the list of pathogenic BEST1 genotypes and the associated clinical diagnosis.

Keywords: BEST1; autosomal recessive bestrophinopathy; best vitelliform macular dystrophy; electrooculogram; mutation analysis.

MeSH terms

  • Bestrophins / genetics*
  • Child
  • Codon, Nonsense*
  • DNA Mutational Analysis
  • Electrooculography
  • Electroretinography
  • Eye Diseases, Hereditary / diagnostic imaging
  • Eye Diseases, Hereditary / genetics*
  • Eye Diseases, Hereditary / physiopathology
  • Family Characteristics
  • Female
  • Fluorescein Angiography
  • Genotype
  • Humans
  • Male
  • Mutation, Missense*
  • Pedigree
  • Phenotype
  • Polymerase Chain Reaction
  • Retina / physiopathology
  • Retinal Diseases / diagnostic imaging
  • Retinal Diseases / genetics*
  • Retinal Diseases / physiopathology
  • Tomography, Optical Coherence
  • Tunisia
  • Vitelliform Macular Dystrophy / diagnostic imaging
  • Vitelliform Macular Dystrophy / genetics*
  • Vitelliform Macular Dystrophy / physiopathology


  • BEST1 protein, human
  • Bestrophins
  • Codon, Nonsense

Supplementary concepts

  • Bestrophinopathy