In EGFR-amplified GBM, clonality of oncogenic coding mutations can vary with the presence or absence of the EGFRvIII isoform.

Sample View of TCGA-06-0157-01A. This tumor has EGFR amplification and one missense mutation (oval), but no vIII isoform as shown by splice junction track. The missense mutation is present at 93% of DNA.

Sample View of TCGA-19-2620-01A. This tumor has EGFR amplification and a missense mutation, and also an SV leading to vIII isoform (splice junction track). The missense mutation is present at only 14% of DNA.