BCR and leukemia: We have now extended this approach to include a model of BCR-FGFR1 induced leukemia were, in contrast to the previous report, mice rapidly developed SCLL syndrome which was similar to the human disease as evidenced by hepatosplenomegaly, fibrosis and leukocytosis with progenitor, myeloid and B-cell neoplasms in the bone marrow and spleen that were transplantable and tumorigenic in secondary recipient mice.