HCC827 cells were exposed in vitro to the irreversible EGFR inhibitor PF00299804 and resistant clones were isolated. These resistant clones (HCC827 PFR) contained an amplification of the MET gene and the growth of the HCC827 PFR cells was inhibited with the combination of PF00299804 and a MET kinase inhibitor. Phenotypically, these HCC827 PFR cells were similar to our previously identified gefitinib resistant HCC827 (HCC827 GR) cells (Engelman et al. Science 2007). In order to compare global genomic changes between HCC827 GR and HCC827 PFR cells and to determine whether the MET amplicon was similar in both drug resistant cells we performed a genome wide SNP analysis. Overall design: Affymetrix SNP arrays were performed according to the manufacturer's directions on DNA extracted from non-small cell lung cancer cell lines. Each sample analyzed in single, with HCC827 serving as the reference sample.