Zhao et al (2009) showed that IDH1 regulates HIF1 expression. Recently, Sanson et al (2009) suggested that the IDH1 mutation might correlate with a glial tumour grade. However, the specific role of the IDH1 mutation in glial tumours, such as astrocytic tumours and secondary glioblastomas is unknown. This evidence concerns the gene IDH1 and glioma.