In patients with diagnosed colorectal carcinoma, the decision for an anti-EGFR antibody therapy is based on routine mutation analysis of kirsten rat sarcoma viral oncogene homolog (KRAS), neuroblastoma RAS viral oncogene homolog, and B-Raf proto-oncogene serine/threonine kinase gene resulting in a valine-to-glutamate change at the residue 600 (Karapetis et al. 2008). The gene discussed is KRAS; the disease is colorectal carcinoma.