Diffuse gliomas include WHO grade 2-3 gliomas. There are no large-scale genomic and transcriptomic expression profiling tests to assist in staging and determining prognosis. Michael Weller et al, Department of Neurosurgery, University Hospital Zurich, Switzerland, published a research paper online in Acta Neuropathol in March 2015 reporting molecular typing of diffuse gliomas based on genomic and transcriptomic expression profiling to predict the prognosis of this tumor. The authors collected 137 diffuse glioma samples, including 61 cases of WHO grade 2 and 76 cases of WHO grade 3, for genomic and transcriptomic expression profiling. Combined with the pathological grading of the patients, the molecular markers such as IDH1 mutation, 1p/19q co-deletion and TERT promoter mutation were integrated with bioinformatics analysis and the prognosis of the patients, unsupervised clustering and typing were performed to determine the molecular subtypes of the 137 gliomas. The tumors were classified into 5 subtypes based on genomic expression profiles, including 3 subtypes with IDH mutations and 2 subtypes with IDH wild type. Based on the transcriptome expression profile, tumors can be classified into 8 subtypes, including 5 subtypes with IDH mutations and 3 subtypes with IDH wild type. It should be noted that the results of these two types of typing were only partially correlated with each other. The genomic molecular typing combined with the clinical prognosis of the patients can further classify diffuse gliomas into three major categories. Patients with IDH mutations combined with 1p/19q co-deletions have the best prognosis; those with IDH wild-type combined with glioblastoma-like genomic alterations, including 7q amplifications, 10q deletions, TERT promoter region mutations, and other proto-oncogene amplifications have the worst prognosis; those with IDH mutations without 1p/19q deletions and IDH wild-type without glioblastoma-like genomic alterations have the worst prognosis. The prognosis of patients with genomic alterations was intermediate between the first two subtypes. The results of this study suggest that molecular typing based on genomic expression profiles and transcriptomic expression profiles can more accurately predict the prognosis of diffuse gliomas.