These assays are paramount since the characteristics of the tumour influence the therapy that is prescribed; tumours with IDH 1 or IDH 2 mutations are less aggressive and respond better to radiotherapy followed by chemotherapy, whereas methylation of the O6-methylguanine deoxyribonucleic acid (DNA) methyltransferase (MGMT) gene predicts a positive response to chemotherapy with alkylating agents [7]. The gene discussed is MGMT; the disease is neoplasm.