To test for any further association other than the IDH-mutation we compared risk allele carriers with non-carriers for common glioma associated oncogenic changes (IDH1/2 and TERT-promoter mutations, and immunohistochemistry for ATRX, TP53, p16INK4A, PTEN, EGFR and MGMT methylation). The gene discussed is CDKN2A; the disease is central nervous system cancer.