Therefore, a meta-analysis was performed to specifically investigate the association with GSTP1 (Ile105Val and Ala114Val), GSTT1 (null/present) and GSTM1 (null/present) variants and the risk of glioma that included data from this case-control study of 724 patients combined with other recently published and relevant studies. Here, GSTM1 is linked to central nervous system cancer.