The MAPK/Extracellular signal-regulated kinase (ERK) signaling pathway is commonly activated in melanoma by mutations in BRAF (in 50% of melanomas), NRAS (10–20%), and less frequently in MEK1 and MEK2 (∼8%) (Davies et al., 2002; Curtin et al., 2005; Murugan et al., 2009; Dutton-Regester and Hayward, 2012). The gene discussed is MAP2K2; the disease is melanoma.