IDH1 and anaplastic astrocytoma: IDH1-R132H/C mutations were found in 7 out of 8 WHO II grade tumours (88%, R132H in six samples and R132C in one sample), 1 out of the 2 anaplastic astrocytomas (50%, R132C), and as expected by the low frequencies reported in literature in none of the GBMs (0%) [8], [9].