Hematopoietic pathways affected by interactions of c-kit and SCF. Differentiation pathways and cellular compartments strongly perturbed in the absence of c-kit are depicted in bold print. Fine print denotes pathways unaffected by lack of c-kit. c-kit plays a more important role in the self-renewal of HSC (A), the expansion of early erythroid (B), and myeloid (C) precursors. It is not clear whether the expansion of prethymic precursors (D) and the colonization of these cells at the thymus (E) require c-kit–mediated signals. c-kit plays little role in B-cell development of both B1 and B2 lineages (G).