Figure 5. LGGs and GBMs with Wild-Type IDH.

Panel A shows the frequency of large-scale copy-number alterations in specific molecular subtypes of LGG, which have been divided according to histologic grade. The University of California, Santa Cruz (UCSC), Cancer Genomics Browser³³ (https://genome-cancer.ucsc.-edu) was used to visualize GISTIC thresholded copy-number calls across the indicated chromosomes. Each vertical line indicates the copy number for an individual sample, colored red (amplification), blue (deletion), or white (normal), at each genomic position. Percentages for the indicated copy-number alteration are shown in the bar graphs on the right. LGGs with wild-type IDH had frequencies of gains and losses similar to those of GBMs with wild-type IDH (from previously published Cancer Genome Atlas data²²) and were distinct from LGGs with mutated IDH. DM/HSR denotes double-minute chromosomes or homogeneously staining regions. Panel B shows the frequencies in the indicated LGG molecular subtypes of mutational events that are commonly found in GBM with wild-type IDH, including LGGs with IDH mutation and 1p/19q codeletion (85 samples), IDH mutation and no codeletion (141), and wild-type IDH (56). SNV denotes single-nucleotide variant, and SV structural variant. Differences in mutational frequency according to tumor grade are shown in Fig. S21 in Supplementary Appendix 1.