title: Complement factor H Y402H and C-reactive protein polymorphism and photodynamic therapy response in age-related macular degeneration.
abstract: OBJECTIVE
  To investigate the association between complement factor H (CFH) and C-reactive protein (CRP) genotypes and response to photodynamic therapy (PDT) treatment for neovascular age-related macular degeneration (AMD).
  
  
  METHODS
  Retrospective cohort study.
  
  
  METHODS
  The study cohort consisted of 273 neovascular AMD patients treated with PDT.
  
  
  METHODS
  Genotypes were determined for the common T-->C single nucleotide polymorphism (SNP) in exon 9 of the CFH gene (rs1061170; Y402H), as well as 9 selected tagging SNPs across the CRP gene (rs2808635, rs1417938, rs1800947, rs1130864, rs1205, rs3093077, rs876538, rs876537, and rs1572970). Visual acuity outcome after PDT was retrospectively calculated and patients were classified as PDT-positive responders or PDT-negative responders. Logistic regression analysis was used to evaluate the association between individual SNPs and PDT treatment response while adjusting for relevant covariates.
  
  
  METHODS
  Response to PDT treatment defined by visual acuity; genotypes of CFH Y402H and CRP polymorphism.
  
  
  RESULTS
  Of the 273 patients, 75 had a positive response after PDT treatment. The frequency of CC genotype of the CFH Y402H polymorphism in the PDT-positive response group was lower than in the negative PDT response group (26.4% vs 31.6%) but this difference failed to reach statistical significance. Two CRP SNPs (rs2808635 and rs876538) were significantly associated with PDT treatment response. Positive treatment response was seen in individuals homozygous for the minor allele of the rs2808635 (GG; odds ratio [OR], 3.92; 95% confidence interval [CI], 1.40-10.97; P = 0.048) and rs876538 (AA; OR, 6.49; 95% CI, 1.65-25.47; P = 0.048) variants after adjusting for relevant covariates. The remaining 7 CRP genetic variants did not reveal any significant association with treatment response.
  
  
  CONCLUSIONS
  Our data did not show significant association between the CFH Y402H polymorphism and PDT treatment response for neovascular AMD; however, CRP genetic variants were associated with a positive response to PDT treatment for neovascular AMD.
authors.affiliation: Lions Eye Institute, Centre for Ophthalmology and Visual Science, University of Western Australia, Perth, Australia.
authors.forename: Xuefeng
authors.initials: X
authors.lastname: Feng
authors.forename: Jing
authors.initials: J
authors.lastname: Xiao
authors.forename: Brooke
authors.initials: B
authors.lastname: Longville
authors.forename: Alexander X J
authors.initials: AX
authors.lastname: Tan
authors.forename: Xia Ni
authors.initials: XN
authors.lastname: Wu
authors.forename: Matthew N
authors.initials: MN
authors.lastname: Cooper
authors.forename: Ian L
authors.initials: IL
authors.lastname: McAllister
authors.forename: Timothy
authors.initials: T
authors.lastname: Isaacs
authors.forename: Lyle J
authors.initials: LJ
authors.lastname: Palmer
authors.forename: Ian J
authors.initials: IJ
authors.lastname: Constable
mesh_terms: D000368:Aged; D002097:C-Reactive Protein / Q000235:genetics*; D020256:Choroidal Neovascularization / Q000188:drug therapy* / Q000235:genetics; D017242:Complement Factor H / Q000235:genetics*; D005260:Female; D005838:Genotype; D006801:Humans; D008268:Macular Degeneration / Q000188:drug therapy* / Q000235:genetics; D008297:Male; D010778:Photochemotherapy; D017319:Photosensitizing Agents / Q000627:therapeutic use; D020641:Polymorphism, Single Nucleotide; D011166:Porphyrins / Q000627:therapeutic use; D012189:Retrospective Studies; D016896:Treatment Outcome; D000077362:Verteporfin; D014792:Visual Acuity
chemical_list: D017319:Photosensitizing Agents; D011166:Porphyrins; D000077362:Verteporfin; D017242:Complement Factor H; D002097:C-Reactive Protein