Subgroup analyses by ethnicity showed there was also no association between GSTP1 Ile105Val</span> polymorphism and glioma</span> risk in mixed populations under recessive model (OR = 1.199, 95%CI = 0.928-1.549, Pheterogeneity = 0.060, P = 0.166) and Caucasian populations (OR = 1.097, 95%CI = 0.885-1.360, Pheterogeneity = 0.186, P = 0.398).
The combined results based on all studies showed that there was no association between any of the GST variants and the risk of glioma (for GSTM1: pooled OR = 1.03; 95 % CI, 0.92-1.15; for GSTT1: pooled OR = 1.12; 95 % CI, 0.90-1.40; for GSTP1 I105V: pooled OR = 0.92; 95 % CI, 0.64-1.31 and for GSTP1 A114V: pooled OR = 1.14; 95 % CI, 0.97-1.34).
The genotype #GA# for rs1695 was recognized to be a protective genotype forglioma (OR, 0.67; 95% CI, 0.47-0.96; P = 0.027), while the genotype #AG# for rs2853676 was shown to be a risk genotype for glioma (OR, 1.50; 95% CI, 1.05-2.15; P = 0.025).
There was evidence of supermultiplicativity of the joint effect of GSTP1 I105V and CYP2E1 RsaI variants on both glioma and acoustic neuroma, even following adjustment of estimates toward a common prior distribution using hierarchical regression models.