Besides polymorphic variations, somatic mutations identified in ErbB genes, including EGFR (Figures 1, 2) greatly influence in the receptor activity and interaction with TKIs, it is of fundamental importance to investigate the cooperation between SNPs and cancer-associated somatic mutations in ErbB genes to better understand the utility of ErbB polymorphisms to predict individual susceptibility to anti-ErbB therapeutics. The gene discussed is EGFR; the disease is cancer.