IDH1 and glioma: In low and high grade gliomas of the present series, the frequency of the SNP rs12435998 was compared with a series of genetic and epigenetic alterations (IDH1/2 somatic mutations, EGFR gene amplification, MGMT promoter hypermethylation, TP53 mutations or TERT promoter mutations [personal data], 1p/19q chromosome status, already published [25–28].