TP53 mutations have been described in approximately 40%–50% of CRC cases (Olivier et al., 2002), and KRAS mutations have been detected in approximately 44% of metastasis CRC patients, with most mutations being identified in codons 12 and 13 of exon 2 (Wong and Cunningham, 2008). The gene discussed is KRAS; the disease is colorectal carcinoma.