title: A novel mutation in the ELOVL4 gene causes autosomal dominant Stargardt-like macular dystrophy.
abstract: OBJECTIVE
  To conduct clinical and genetic studies in a European family with autosomal dominant Stargardt-like macular dystrophy (adSTGD-like MD) and to investigate the functional consequences of a novel ELOVL4 mutation.
  
  
  METHODS
  Ophthalmic examination and mutation screening by direct sequencing of the ELOVL4 gene was performed in two affected individuals. Wild-type and mutant ELOVL4 genes were expressed as enhanced green fluorescent protein (EGFP) fusion proteins in transient transfection in NIH-3T3 and HEK293 cells. To determine the subcellular localization of ELOVL4, an endoplasmic-reticulum (ER)-specific marker for pDsRed2-ER was cotransfected with ELOVL4 constructs. Transfected cells were viewed by confocal microscopy. Western blot analysis was performed to assess protein expression using an anti-GFP antibody.
  
  
  RESULTS
  Affected patients exhibited macular atrophy with surrounding flecks characteristic of adSTGD-like MD. A novel ELOVL4 p.Tyr270X mutation was detected in affected individuals. In cell-transfection studies, wild-type ELOVL4 localized preferentially to the ER. In contrast, the mutant protein appeared to be mislocalized within transfected cells.
  
  
  CONCLUSIONS
  In a European family with adSTGD-like MD, a novel ELOVL4 mutation was found to underlie the disorder. Transfection studies indicated that, unlike wild-type ELOVL4, the mutant protein does not localize to the ER but rather appears to be sequestered elsewhere in an aggregated pattern in the cytoplasm. Further analysis of the function of normal and mutant ELOVL4 will provide insight into the mechanism of macular degeneration.
authors.affiliation: Department of Human Genetics, Radboud University Nijmegen Medical Centre, Geert Grooteplein 10, PO Box 9101, 6500 HB Nijmegen, The Netherlands. a.maugeri@antrg.umcn.nl
authors.forename: Alessandra
authors.initials: A
authors.lastname: Maugeri
authors.forename: Francoise
authors.initials: F
authors.lastname: Meire
authors.forename: Carel B
authors.initials: CB
authors.lastname: Hoyng
authors.forename: Carolien
authors.initials: C
authors.lastname: Vink
authors.forename: Nicole
authors.initials: N
authors.lastname: Van Regemorter
authors.forename: Goutam
authors.initials: G
authors.lastname: Karan
authors.forename: Zhenglin
authors.initials: Z
authors.lastname: Yang
authors.forename: Frans P M
authors.initials: FP
authors.lastname: Cremers
authors.forename: Kang
authors.initials: K
authors.lastname: Zhang
mesh_terms: D000293:Adolescent; D000328:Adult; D001284:Atrophy; D015153:Blotting, Western; D002460:Cell Line; D018388:Codon, Terminator; D003593:Cytoplasm / Q000378:metabolism; D004721:Endoplasmic Reticulum / Q000378:metabolism; D005136:Eye Proteins / Q000235:genetics* / Q000378:metabolism; D005260:Female; D005799:Genes, Dominant; D049452:Green Fluorescent Proteins; D006801:Humans; D008164:Luminescent Proteins; D008266:Macula Lutea / Q000473:pathology; D008268:Macular Degeneration / Q000235:genetics* / Q000473:pathology / Q000503:physiopathology; D008565:Membrane Proteins / Q000235:genetics* / Q000378:metabolism; D018613:Microscopy, Confocal; D009154:Mutation; D010375:Pedigree; D014018:Tissue Distribution; D014162:Transfection; D014443:Tyrosine; D014792:Visual Acuity
chemical_list: D018388:Codon, Terminator; C418975:ELOVL4 protein, human; D005136:Eye Proteins; D008164:Luminescent Proteins; D008565:Membrane Proteins; D049452:Green Fluorescent Proteins; D014443:Tyrosine