The use of iPSCs in modeling for acquired blood disease. Bone marrow samples from patients with acquired blood diseases can be used to obtain mutation-free mesenchymal stem cells (MSCs) and CD34⁺ cells or other types of hematopoietic progenitors (HPs) carrying disease-associated mutation. Alternatively, diseased peripheral blood CD34⁺ cells and fibroblasts or other types of cells lacking mutation from the same patient can be used. By reprogramming cells with or without genetic abnormality from the same patient, iPSCs with the same genetic background but different in expression of mutation can be generated. Using an in vitro differentiation system, hematopoietic precursors at different stages of maturation and terminally differentiated cells can be obtained for studies of disease pathogenesis. Transplantation of de novo generated cells with neoplasia-specific mutation into immunocompromised mice can be used to address emergence of blood cancer stem cells. Drug screening and discovery is another obvious and immediate benefit of iPSC technology for development of new therapies for blood diseases.