While XIST and SFRP2 were the best discriminatory genes between DA and AA gliomas, additional differences between these tumor subtypes and GBM were found, including overexpression of the DPP10, ETNPPL and SH3GL2 genes and underexpression of CHI3L1, VEGFA and IGF genes in the former two tumor types, in close association with unique chromosomal location profiles. Here, IGF1 is linked to glioma.