E478 xenografts contain the IDH1-R132H mutation. A) E478 xenografts contain the G=> A mutation as shown by direct sequencing. B) Micrograph of a E478 xenograft in mouse brain, stained with the IDH1-R132H-specific antibody, bar =100 μm. C) Curves of time to sacrifice of mice in various passages of the E478 line, P0 being the first transplantation of surgically-obtained tumor material, directly from the patient in nude mice. D) Comparison of array CGH profiles of the tumor of the patient (blue) and a derived xenograft (P25, brown). The losses of chromosome arms 1p and 19q, typical for oligodendroglioma, are indicated by arrows in the profile of the patient tumor. All genetic aberrations that were present in the original tumor, are present in the profile of the xenografts as well, with a few additional aberrations in the xenograft. Further details are presented in Additional file 2: Figure S1.