In this presentation, Jennifer Morrissette, PhD, of Penn Medicine’s Center for Personalized Diagnostics, examines the genetic sequencing of glioblastoma multiforme (GBM), among the earliest genomes to be collected by the Cancer Genome Atlas. Dr. Morrissette expands upon the frequency, heterogeneity, overlap and amplification of EGFR mutations in GBM and characterizes the subclonal structure of the tumors for their predictive value.