IDH1 and central nervous system cancer: As to the three most important markers (IDH, ATRX and 1p19q), we found the same results as ISN-Haarlem consensus and the latest WHO CNS guildline, the loss of nuclear ATRX expression was significantly correlation with the IDH1/2 mutations status in grade II gliomas (101/124, 81.45%, P<0.001), and ATRX was seemed mutually exclusive with the total 1p/19q codeletion.