BRAF is a human gene that makes a protein called B-Raf.The gene is also referred to as proto-oncogene B-Raf and v-Raf murine sarcoma viral oncogene homolog B, while the protein is more formally known as serine/threonine-protein kinase B-Raf.he V600E mutation of the BRAF gene has been associated with hairy cell leukemia in numerous studies and has been suggested for use in screening for Lynch syndrome to reduce the number of patients undergoing unnecessary MLH1 sequencing.