After analyzing the associations between 91 IFs and GBM risk, we found suggestive evidence that 3 IFs were associated with GBM using the IVW method (p=0.04 for Fractalkine levels; p=0.03 for C-X-C motif chemokine 6 levels and p=1.00×10-3 for FGF21). Here, FGF21 is linked to glioblastoma.