Raf proteins and cancer: B-Raf is identified as a mutational target.

A recent report has shown that activating mutations in the BRAF gene are present in a large percentage of human malignant melanomas and in a proportion of colon cancers. The vast majority of these mutations represent a single nucleotide change of T-A at nucleotide 1796 resulting in a valine to glutamic acid change at residue 599 within the activation segment of B-Raf. This exciting new discovery is the first time that a direct association between any RAF gene and human cancer has been reported.