title: Association of OPA1 polymorphisms with NTG and HTG: a meta-analysis.
abstract: BACKGROUND
  Genetic polymorphisms of the Optic atrophy 1 gene have been implicated in altering the risk of primary open angle glaucoma (POAG), especially the susceptibility to normal tension glaucoma (NTG), but the results remain controversial.
  
  
  METHODS
  Multiple electronic databases (up to January 20, 2012) were searched independently by two investigators. A meta-analysis was performed on the association between Optic atrophy 1 polymorphisms (rs 166850 and rs 10451941) and normal tension glaucoma (NTG)/high tension glaucoma (HTG). Summary odds ratios (ORs) and 95% confidence intervals (CI) were estimated.
  
  
  RESULTS
  Seven studies of 713 cases and 964 controls for NTG and five studies of 1200 cases and 971 controls for HTG on IVS8+4C>T (rs 166850) and IVS8+32T>C (rs10451941) were identified. There were significant associations between the OPA1 rs10451941polymorphism and NTG susceptibility for all genetic models(C vs. T OR = 1.26, 95% CI 1.09-1.47, p = 0.002; CC vs. TT: OR = 1.52, 95% CI 1.04-2.20, p = 0.029; CC vs. CT+TT: OR = 1.64, 95% CI 1.16-2.33, p = 0.005; CC+CT vs. TT: OR = 1.21, 95% CI 1.02-1.44, p = 0.032). However, no evidence of associations was detected between the OPA1 IVS8+32C>T polymorphism and POAG susceptibility to HTG. Similarly, clear associations between the rs 166850 variant and NTG were observed in allelic and dominant models (T vs. C OR = 1.52, 95% CI 1.16-1.99, p = 0.002; TT+TC vs. CC OR = 1.50, 95% CI 1.13-2.01, p = 0.006) but not to HTG. In subgroup analyses by ethnicity, we detected an association between both OPA1 polymorphisms and risk for NTG in Caucasians but not in Asians. By contrast, no significant findings were noted between OPA1 variants for HTG, either in Caucasians or in Asians.
  
  
  CONCLUSIONS
  Both the IVS8+4C>T and IVS8+32T>C variants may affect individual susceptibility to NTG. Moreover, stratified analyses for NTG detecting the effects of both OPA1 polymorphisms seemed to vary with ethnicity. Further investigations are needed to validate the association.
authors.affiliation: Tianjin Medical University, Tianjin, China.
authors.forename: Yatu
authors.initials: Y
authors.lastname: Guo
authors.forename: Xia
authors.initials: X
authors.lastname: Chen
authors.forename: Hongtuan
authors.initials: H
authors.lastname: Zhang
authors.forename: Ningdong
authors.initials: N
authors.lastname: Li
authors.forename: Xiong
authors.initials: X
authors.lastname: Yang
authors.forename: Wenbo
authors.initials: W
authors.lastname: Cheng
authors.forename: Kanxing
authors.initials: K
authors.lastname: Zhao
mesh_terms: D000483:Alleles; D020558:GTP Phosphohydrolases / Q000235:genetics*; D056726:Genetic Association Studies; D020022:Genetic Predisposition to Disease; D005901:Glaucoma / Q000235:genetics*; D005902:Glaucoma, Open-Angle / Q000235:genetics; D006801:Humans; D057066:Low Tension Glaucoma / Q000235:genetics*; D008957:Models, Genetic; D020641:Polymorphism, Single Nucleotide / Q000235:genetics*; D017594:Publication Bias; D012307:Risk Factors
chemical_list: D020558:GTP Phosphohydrolases; C415198:OPA1 protein, human