WNK2 and melanoma: An important molecular pathway highlighted, due to differential DNA methylation in RAF1, is the mitogen-activated protein kinase/extracellular signal-regulated kinase pathway that includes BRAF. BRAF mutations are found in approximately 50% of all melanoma tumors and are of significant clinical utility as major therapeutic decisions are made according to the presence or absence of mutations in this gene (Flaherty et al., 2010).