In this study, HLA-DRB1*08:03 (OR 0.32 CI 0.11–0.98) was significantly related to decreased risk for GBM development; haplotype HLA-DRB1*08:03-DQB1*06:01 was also related to decreased risk of GBM development, although the OR was not statistically significant (OR 0.34 0.11–1.04). This evidence concerns the gene HLA-DRB1 and glioblastoma.