KDR and central nervous system cancer: Our meta-analysis from a total of five studies (n = 6010) showed that the C allele of KDR/VEGFR (rs2071559) gene polymorphism was associated with a higher risk of developing gliomas than the T allele [OR 1.41 (95% CI 1.27–1.57), p < 0.001, I2 = 0%, random-effects models] (Figure 2C).