title: Cone ERG responses in patients with Smith-Lemli-Opitz Syndrome (SLOS).
abstract: OBJECTIVE
  To evaluate cone and cone-driven retinal function in patients with Smith-Lemli-Opitz syndrome (SLOS), a condition characterized by low cholesterol. Rod and rod-driven function in patients with SLOS are known to be abnormal.
  
  
  METHODS
  Electroretinographic (ERG) responses to full-field stimuli presented on a steady, rod suppressing background were recorded in 13 patients who had received long-term cholesterol supplementation. Cone photoresponse sensitivity (S(CONE)) and saturated amplitude (R(CONE)) parameters were estimated using a model of the activation of phototransduction, and post-receptor b-wave and 30 Hz flicker responses were analyzed. The responses of the patients were compared to those of control subjects (N = 13).
  
  
  RESULTS
  Although average values of both S(CONE) and R(CONE) were lower than in controls, the differences were not statistically significant. Post-receptor b-wave amplitude and implicit time and flicker responses were normal.
  
  
  CONCLUSIONS
  The normal cone function contrasts with the significant abnormalities in rod function that were found previously in these same patients. Possibly, cholesterol supplementation has a greater protective effect on cones than on rods as has been demonstrated in the rat model of SLOS.
authors.affiliation: Department of Ophthalmology, Children's Hospital Boston, Harvard Medical School, 300 Longwood Avenue, Boston, MA 02115, USA.
authors.forename: Deirdre
authors.initials: D
authors.lastname: Garry
authors.forename: Ronald M
authors.initials: RM
authors.lastname: Hansen
authors.forename: Anne
authors.initials: A
authors.lastname: Moskowitz
authors.forename: Ellen R
authors.initials: ER
authors.lastname: Elias
authors.forename: Mira
authors.initials: M
authors.lastname: Irons
authors.forename: Anne B
authors.initials: AB
authors.lastname: Fulton
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D002784:Cholesterol / Q000097:blood; D004596:Electroretinography; D005260:Female; D006801:Humans; D008297:Male; D017949:Retinal Cone Photoreceptor Cells / Q000502:physiology*; D019082:Smith-Lemli-Opitz Syndrome / Q000503:physiopathology*; D055815:Young Adult
chemical_list: D002784:Cholesterol