KDR and glioma: Our meta-analysis from a total of six studies (n = 2697) showed that the genetic model consisting of CC genotypes of KDR/VEGFR2 (rs2071559) gene polymorphism was associated with a higher risk of gliomas than the model consisting of TT genotypes [OR 1.78 (95% CI 1.42–2.24), p < 0.001, I2 = 32%, random-effects models] (Figure 3A).