title: The association between complement component 2/complement factor B polymorphisms and age-related macular degeneration: a HuGE review and meta-analysis.
abstract: The authors performed a systematic review of the association of complement component 2(C2)/complement factor B (CFB) gene polymorphisms with age-related macular degeneration (AMD). In total, data from 19 studies published between 2006 and 2011 were pooled for 4 polymorphisms: rs9332739 and rs547154 in the C2 gene and rs4151667 and rs641153 in the CFB gene. Data extraction and assessments for risk of bias were independently performed by 2 reviewers. Allele frequencies and allele and genotypic effects were pooled. Heterogeneity and publication bias were explored. Pooled minor allele frequencies for all 4 SNPs were between 4.7% and 9.6% for all polymorphisms, except for an Indian population in which the C allele at rs9332739 was the major allele. For the C2 polymorphisms, the minor C allele at rs9332739 and the minor T allele at rs547154 carried estimated relative risks (odds ratios) of 0.55 (95% confidence interval (CI): 0.46, 0.65) and 0.47 (95% CI: 0.39, 0.57), respectively. For the CFB polymorphisms, the minor A alleles at rs4151667 and rs614153 carried estimated risks of 0.54 (95% CI: 0.45, 0.64) and 0.41 (95% CI: 0.34, 0.51), respectively. These allele effects contributed to an absolute lowering of the risk of all AMD in Caucasian populations by 2.0%-6.0%. This meta-analysis provides a robust estimate of the protective association of C2/CFB with AMD.
authors.affiliation: Section for Epidemiology and Biostatistics, Ramathibodi Hospital, Mahidol University, Bangkok, Thailand. ammarin.tha@mahidol.ac.th
authors.forename: Ammarin
authors.initials: A
authors.lastname: Thakkinstian
authors.forename: Mark
authors.initials: M
authors.lastname: McEvoy
authors.forename: Usha
authors.initials: U
authors.lastname: Chakravarthy
authors.forename: Subhabrata
authors.initials: S
authors.lastname: Chakrabarti
authors.forename: Gareth J
authors.initials: GJ
authors.lastname: McKay
authors.forename: Euijung
authors.initials: E
authors.lastname: Ryu
authors.forename: Giuliana
authors.initials: G
authors.lastname: Silvestri
authors.forename: Inderjeet
authors.initials: I
authors.lastname: Kaur
authors.forename: Peter
authors.initials: P
authors.lastname: Francis
authors.forename: Takeshi
authors.initials: T
authors.lastname: Iwata
authors.forename: Masakazu
authors.initials: M
authors.lastname: Akahori
authors.forename: Astrid
authors.initials: A
authors.lastname: Arning
authors.forename: Albert O
authors.initials: AO
authors.lastname: Edwards
authors.forename: Johanna M
authors.initials: JM
authors.lastname: Seddon
authors.forename: John
authors.initials: J
authors.lastname: Attia
mesh_terms: D044466:Asian People; D003175:Complement C2 / Q000235:genetics*; D011415:Complement Factor B / Q000235:genetics*; D005787:Gene Frequency; D005819:Genetic Markers; D055106:Genome-Wide Association Study; D006801:Humans; D008268:Macular Degeneration / Q000208:ethnology / Q000235:genetics*; D015233:Models, Statistical; D016017:Odds Ratio; D020641:Polymorphism, Single Nucleotide; D044465:White People
chemical_list: D003175:Complement C2; D005819:Genetic Markers; D011415:Complement Factor B