IDH1 and neoplasm: Therefore, no difference in the levels of trimethylated H3K4, H3K9 or H3K27 could be detected between IDH mutant and wildtype central cartilaginous tumours (Fig. 3b, d, f, p = 0.54, 0.46 and 0.78, respectively), nor between central and peripheral chondrosarcomas (data not shown).