title: Vascular endothelial growth factor (VEGF-634G/C) polymorphism and retinopathy of prematurity: a meta-analysis.
abstract: OBJECTIVE
  Vascular endothelial growth factor polymorphism (VEGF-634G/C, rs 2010963) has been considered a risk factor for the development of retinopathy of prematurity (ROP). However, the results remain controversial. Therefore, the aim of the present meta-analysis was to determine the association between VEGF-634G/C polymorphism and ROP risk.
  
  
  METHODS
  Published literature from PubMed and other databases were retrieved. All studies evaluating the association between VEGF-634G/C polymorphism and ROP risk were included. Pooled odds ratio (OR) and 95% confidence interval (CI) were calculated using random or fixed effects model. A total of six case-control studies including 355 cases and 471 controls were included.
  
  
  RESULTS
  By pooling all the studies, we found that VEGF-634G/C polymorphism was not associated with ROP risk at co-dominant and allele levels and no association was also found in dominant and recessive models. While stratifying on ethnicity level no association was observed in Caucasian and Asian population.
  
  
  CONCLUSIONS
  This meta-analysis suggests that VEGF-634G/C polymorphism may not be associated with ROP risk, the association between single VEGF-634G/C polymorphism and ROP risk awaits further investigation.
authors.affiliation: Department of Ocular Biochemistry, Dr. Rajendra Prasad Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, India.
authors.forename: Manzoor Ahmad
authors.initials: MA
authors.lastname: Malik
authors.affiliation: Department of Ocular Biochemistry, Dr. Rajendra Prasad Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, India.
authors.forename: Swati
authors.initials: S
authors.lastname: Shukla
authors.affiliation: Vitreo-Retina, Ocular Trauma and Retinopathy of Prematurity Services, Dr. Rajendra Prasad Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, India.
authors.forename: Shorya Vardhan
authors.initials: SV
authors.lastname: Azad
authors.affiliation: Department of Ocular Biochemistry, Dr. Rajendra Prasad Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, India.
authors.forename: Jasbir
authors.initials: J
authors.lastname: Kaur
keywords: Meta-analysis; Polymorphism; ROP; VEGF