title: Autosomal dominant cone-rod retinal dystrophy (CORD6) from heterozygous mutation of GUCY2D, which encodes retinal guanylate cyclase.
abstract: OBJECTIVE
  To describe the clinical features of autosomal dominant cone-rod retinal dystrophy (CRD) in a British family mapping to chromosome 17p12-p13 (CORD6), with a heterozygous mutation (Glu837Asp/ Arg838Ser) of GUCY2D.
  
  
  METHODS
  A prospective, clinical family survey.
  
  
  METHODS
  Ten affected members of a family with autosomal dominant CRD.
  
  
  METHODS
  Full clinical examinations were undertaken. Selected affected family members underwent electrophysiologic evaluation, scotopic static perimetry, dark adaptometry, and color vision assessment.
  
  
  METHODS
  Clinical appearance and electroretinographic responses.
  
  
  RESULTS
  Typical clinical and electroretinographic features of childhood-onset CRD were recorded. In addition, moderate myopia and pendular nystagmus were seen in affected individuals. Color vision assessment in the youngest affected individual showed no color discrimination on a tritan axis, but retention of significant red-green discrimination. Electronegative electroretinogram responses were seen on electrophysiology in the only young family member examined.
  
  
  CONCLUSIONS
  The phenotype associated with GUCY2D CRD is clinically distinct from that associated with other dominant CRD loci. Unusual electroretinographic responses may indicate that this mutation of GUCY2D is associated with early defects in photoreceptor synaptic transmission to second-order neurons.
authors.affiliation: Department of Clinical Ophthalmology, Moorfields Eye Hospital, London, England.
authors.forename: K
authors.initials: K
authors.lastname: Gregory-Evans
authors.forename: R E
authors.initials: RE
authors.lastname: Kelsell
authors.forename: C Y
authors.initials: CY
authors.lastname: Gregory-Evans
authors.forename: S M
authors.initials: SM
authors.lastname: Downes
authors.forename: F W
authors.initials: FW
authors.lastname: Fitzke
authors.forename: G E
authors.initials: GE
authors.lastname: Holder
authors.forename: M
authors.initials: M
authors.lastname: Simunovic
authors.forename: J D
authors.initials: JD
authors.lastname: Mollon
authors.forename: R
authors.initials: R
authors.lastname: Taylor
authors.forename: D M
authors.initials: DM
authors.lastname: Hunt
authors.forename: A C
authors.initials: AC
authors.lastname: Bird
authors.forename: A T
authors.initials: AT
authors.lastname: Moore
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002874:Chromosome Mapping; D002886:Chromosomes, Human, Pair 17 / Q000235:genetics*; D003117:Color Vision Defects / Q000175:diagnosis; D004596:Electroretinography; D005260:Female; D005799:Genes, Dominant / Q000235:genetics*; D008040:Genetic Linkage; D006162:Guanylate Cyclase / Q000235:genetics*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009216:Myopia / Q000175:diagnosis; D009759:Nystagmus, Pathologic / Q000175:diagnosis; D010375:Pedigree; D020419:Photoreceptor Cells, Vertebrate / Q000201:enzymology* / Q000473:pathology; D017354:Point Mutation; D011446:Prospective Studies; D012162:Retinal Degeneration / Q000175:diagnosis / Q000201:enzymology / Q000235:genetics*; D014785:Vision, Ocular / Q000235:genetics; D014792:Visual Acuity
chemical_list: D006162:Guanylate Cyclase