BRAF and melanoma: The RAS/MAP kinase pathway has attracted attention because activating mutations of the BRAF serine/threonine kinase has been detected in more than 50% of melanomas; in particular, the most common BRAF mutation (nearly, 90% of cases) is the T1799A point mutation in exon 15 within the kinase domain, in which a T → A transversion converts glutamic acid for valine at the 600 position of the amino acid sequence (BRAFV600E) and constitutively activates the protein.