We also observed particular instances of the selectively amplified alleles driving higher expression in DOCK4 and EGFR. DOCK4 was originally isolated in a screen to identify homozygous genomic deletions during tumor progression in a mouse model and is part of a larger family of atypical guanine exchange factor (GEF) for Rho family GTPases [23]. Here, EGFR is linked to neoplasm.