C-MYB was the first to be discovered when it was found to be the oncogene present in avian myeloblastosis virus, which causes acute myeloblastic leukemia and can transform hematopoietic cells in culture; A- and B-MYB were subsequently cloned via homology to C-MYB (Roussel et al., 1979; Lam et al., 1992). The gene discussed is MYB; the disease is acute myeloid leukemia.