BRAF and melanoma: To date, >50 distinct mutations in BRAF have been identified, however, ~90% of BRAF mutants in melanoma are single-base transitions (T>A) at position 1,799, leading to the substitution of glutamic acid for valine at codon 600 of the BRAF protein (p.V600E) (5,10,11), which leads to a 500-fold increase in its kinase activity.