The first was at chromosome 10q11.21 and reflected a single amplicon, breaking within the genes RET and CSGALNACT2 such that we propose a hypothetical fusion gene encompassing the 5′ regulatory regions of CSGALNACT2 and the 3′ kinase domain of RET. In order to determine the precise breakpoints to allow validation of this novel fusion, we designed custom oligonucleotide arrays spanning the amplicon in order to carry out high-resolution array CGH on the reference case HGG139, a relapse sample of glioblastoma in which this genomic event was not present in the primary tumour. Here, RET is linked to glioblastoma.