Of the 60 oligodendroglial (1p/19q codeleted) tumours, 49 retained ATRX immunohistochemical expression and 11 had a non-conclusive staining; 57 had a negative and 3 had a positive P53 staining; 58 lost and 2 retained H3K27me3 expression (Figs. 1 and 2; Supplementary Figure 1). Here, ATRX is linked to neoplasm.