title: Homozygous c.1937+1G>A splice-site variant of the ABCA4 gene is associated with Stargardt disease.
abstract: OBJECTIVE
  To report the phenotype of homozygous ABCA4 c.1937+1G>A splice-site variant associated with Stargardt disease.
  
  
  METHODS
  Two siblings, a 10-year-old boy and a 32-year-old woman, born from consanguineous parents, presented with central vision loss and macular pigmentary atrophic changes suggestive of Stargardt disease. After genetic counselling, ABCA4 gene analysis was performed.
  
  
  RESULTS
  The 2 siblings affected were shown to be homozygous for the c.1937+1G>A splice junction variant of the ABCA4 gene. Both parents were heterozygous for the same mutation; they were asymptomatic and the fundus examination revealed a normal appearance.
  
  
  CONCLUSIONS
  Thus far, ABCA4 c.1937+1G>A splice-site variant was shown to cause retinitis pigmentosa when in hemizygosity and Stargardt disease when present on one allele. In this family two sibs homozygous for the ABCA4 c.1937+1G>A splice-site variant have a less severe phenotype of Stargardt disease. This observation provides useful information for the diagnosis and counseling of patients with this ABCA4 variant.
authors.affiliation: Department of Surgical Sciences, Eye Clinic, University of Torino, Torino - Italy.
authors.forename: Chiara M
authors.initials: CM
authors.lastname: Eandi
authors.forename: Federico M
authors.initials: FM
authors.lastname: Grignolo
authors.forename: Ilaria
authors.initials: I
authors.lastname: Passerini
authors.forename: Cristiana
authors.initials: C
authors.lastname: Marchese
mesh_terms: D018528:ATP-Binding Cassette Transporters / Q000235:genetics*; D000328:Adult; D002648:Child; D003241:Consanguinity; D004252:DNA Mutational Analysis; D005260:Female; D006720:Homozygote; D006801:Humans; D008268:Macular Degeneration / Q000175:diagnosis / Q000235:genetics; D008297:Male; D017354:Point Mutation; D016133:Polymerase Chain Reaction; D020033:Protein Isoforms / Q000235:genetics; D035781:Siblings; D000080362:Stargardt Disease; D041623:Tomography, Optical Coherence; D014792:Visual Acuity / Q000502:physiology
chemical_list: C056475:ABCA4 protein, human; D018528:ATP-Binding Cassette Transporters; D020033:Protein Isoforms