IDH1 and astrocytoma (excluding glioblastoma): In the case of non-GBM SNPs rs11196067 showed the strongest association with grade II glioma (P=3.2 × 10−5) and TP53 non-mutated glioma (P=5.82 × 10−5); rs648044 with grade II oligodendroglioma (P=0.026) and 10q non-deleted glioma (P=0.006); rs1801591 with grade II astrocytoma (P=0.001) and IDH1/IDH2 mutated glioma (P=0.005) and rs12230172 with grade II oligodendroglioma (P=0.009), IDH1/IDH2 mutated (P=0.009) and 10q non-deleted glioma (P=0.003).