Considering the RAS/MAPK pathway (54,55) and BCR-ABL1 fusion (56) both play important roles in chronic myeloid leukemia, and BRAF is a key factor of the RAS/MAPK pathway (57), our findings indicate the diverse patterns of clonal selection and mutual exclusion of driver mutations in chronic myeloid leukemia. The gene discussed is BRAF; the disease is chronic myelogenous leukemia, BCR-ABL1 positive.