Deletion of floxed CBL with murine mammary tumor virus (MMTV)-Cre on a CBL-B null background led to a myeloproliferative disease due to CBL deletion in hematopoietic stem cells (HSCs), but such a phenotype was not observed when CBL alone or CBL-B alone were deleted [36, 37]. This evidence concerns the gene CBL and myeloproliferative disorder.